Alert or Illegal

[ArtK78]

I have read the posts in this thread with some interest.

 

While I don't mean to insult any of the posters in this thread, I can't help but think that this is a tremendous waste of time.

 

Statements to the contrary notwithstanding, the ACBL position on opening a non-conventional 1NT with a singleton is quite clear - it is permitted as long as there is no partnership agreement that this will be done, and there cannot be any conventional method for determining that the opener had a singleton. Can I cite chapter and verse on this? No.

 

If a partnership opens a non-conventional 1NT with a singleton frequently (and three times in one session certainly would come under that heading) there is a presumed partnership agreement, and the partnership will be subject to penalties. Can I cite chapter and verse on this? No.

 

Whether you agree or disagree with the ACBL position on opening 1NT with a singleton is not really the issue. It is what it is. You might as well be arguing that gravity should not be in effect on Thursdays.

 

Again, this is in no way meant to disparage any of the posters in this thread. But you must have something better to do.

[hrothgar]

If a partnership opens a non-conventional 1NT with a singleton frequently (and three times in one session certainly would come under that heading) there is a presumed partnership agreement, and the partnership will be subject to penalties.  Can I cite chapter and verse on this?  No.

I tried to raise this point before and it got glossed over:

 

If you look at any large data set, you're going to find some weird looking *****. More too the point, if you play enough sessions of bridge, you're going to run into sessions where something looks off.

 

The fact that a given patnership opened 1NT with a singleton three times in one session is an interesting factoid. If anyone actually cared that these dastardly individuals are opening 1NT with a singleton, this results from this session might even warrant looking at a broader set of hands.

 

However, this occurence doesn't prove anything.

 

Consider the following analogy:

 

I grab a quarter from my pocket.

I flip it 100 times and record the number of times that it turns up heads versus tails.

I end up observing a grand total of 52 heads and 48 tails.

All fine and dandy

 

I decide to repeat this same experiment another 99 times using different quarters, each time recording the number of heads and tails that I see.

 

In general, I see something fairly close to a 50-50 distribution.

Sometimes I see more tails than heads.

Sometimes I see more heads that tails. But most of the observations are pretty 50-50

 

However, one of the quarters acts a bit weird.

I end up observing 35 Heads and 65 tails.

This is three standard deviations away from the mean...

Kind of a freaky occurrence.

 

Have I found a "loaded" quarter?

 

The answer is probably not: It's not at all surprising to see 100 trials produce an event three standard deviations away from the norm... (If you're looking at normally distributed data, you expect to see

 

68% of the observations within one standard deviation of the norm

95% of the observations within two standard deviations of the norm

99.7% of the observations within three standard deviations of the norm

 

(This is even referred to as the 68 - 95 - 99.7 "rule")

 

What I am trying to get across is the following:

 

Large data sets can be very dangerous...

If you search through a large enough data set you're almost guaranteed to some pretty freaky looking *****, even if absolutely nothing suspicious is happening.

 

Or, more specifically, if you plan enough sessions of bridge, you shouldn't be surprised to see one where you open 1NT with a singleton two, maybe even three times...

[jdonn]

If a partnership opens a non-conventional 1NT with a singleton frequently (and three times in one session certainly would come under that heading) there is a presumed partnership agreement, and the partnership will be subject to penalties.  Can I cite chapter and verse on this?  No.

I tried to raise this point before and it got glossed over:

Of course you are technically correct, I didn't mean to be the first to gloss over this point. However, 3 times in one session is so unlikely if you don't generally open 1NT with a singleton with enough frequency to alert it that I don't think you will be wrong once in ten lifetimes if you force such a partnership to alert / change their methods / whatever.

[hrothgar]

Of course you are technically correct, I didn't mean to be the first to gloss over this point. However, 3 times in one session is so unlikely if you don't generally open 1NT with a singleton with enough frequency to alert it that I don't think you will be wrong once in ten lifetimes if you force such a partnership to alert / change their methods / whatever.

I'm not sure about the relative frequencies.

 

Mini NTs are much more common than strong NT openings. This might be enough to push things into the realm of the plausible.

 

Here's something that I would hate to see happen...

 

Let's assume that two different partnerships are playing a style in their 1NT opening can contain a stiff

 

Partnership A plays a traditional strong NT system.

15% of the hands that they open 1NT contain a stiff

 

Partnership B plays a weak NT system

5% of the hands that they open contain a stiff

 

Partnership A is able to happily use their system because the low frequency of NT opener masks the high frequency that the hand contains a stiff. Partnership B gets crucified because high frequency of the their NT opening outweighs the relatively low frequency that they do so with a singleton.

 

As I noted originally, I'd really want to be able to look at a large set of hands and see what does/does not get opened 1NT before trying to reach any kind of conclusion.

[jdonn]

Our of curiosity, what is the minimum amount of times in one session of bridge that a pair playing this notrump range could open 1NT with a singleton that you think would be adequate to require such a pair alert their 1NT opener? How about if playing 15-17?

[hrothgar]

Our of curiosity, what is the minimum amount of times in one session of bridge that a pair playing this notrump range could open 1NT with a singleton that you think would be adequate to require such a pair alert their 1NT opener? How about if playing 15-17?

I'm not sure that I agree with the (proposed) metric.

 

I think that the decision to alert 1NT should be based on the percentage of 1NT openings that contain a singleton. I don't think that the frequency of the NT opening should factor in to the decision.

 

The frequency of the NT opening would (obvously) impact the frequency that a pair needs to alert said opening; however, this strikes me as a second order effect.

[jdonn]

Well I was more going for a gut feeling than a calculation. Although actually I don't think this would be a very difficult calculation to perform, someone would just have to want to bother doing the work and making the necessary assumptions (at what % of notrump openings do you have to start alerting?)

[ArtK78]

Mini NTs are much more common than strong NT openings. This might be enough to push things into the realm of the plausible.

 

Here's something that I would hate to see happen...

 

Let's assume that two different partnerships are playing a style in their 1NT opening can contain a stiff

 

Partnership A plays a traditional strong NT system.

15% of the hands that they open 1NT contain a stiff

 

Partnership B plays a weak NT system

5% of the hands that they open contain a stiff

 

Partnership A is able to happily use their system because the low frequency of NT opener masks the high frequency that the hand contains a stiff. Partnership B gets crucified because high frequency of the their NT opening outweighs the relatively low frequency that they do so with a singleton.

 

As I noted originally, I'd really want to be able to look at a large set of hands and see what does/does not get opened 1NT before trying to reach any kind of conclusion.

I don't agree with your premise.

 

It is no doubt true that hands meeting the requirements for opening a mini-NT are more common than hands meeting the requirements for opening a traditional strong 1NT.

 

However, the opportunity to open a mini-NT is much less frequent, as it is far more likely that there will be an opening bid of some sort in front of the hand holding the mini-NT opener.

 

When one holds a traditional strong 1NT opening hand, the chances of someone else opening the bidding in front of your hand is much less.

 

Furthermore, the vast majority of players who play a mini-NT do so only in 1st and 2nd positions, for obvious reasons.

 

So, if one were to compare the number of times a mini-NT hand comes up when that hand actually has the opportunity to open a mini-NT vs. the times that a strong 1NT opening comes up and that hand has the opportunity to open a strong 1NT, I suspect that you will find the numbers to be much closer to equal than you would have originally thought.

[hrothgar]

I don't agree with your premise.

 

It is no doubt true that hands meeting the requirements for opening a mini-NT are more common than hands meeting the requirements for opening a traditional strong 1NT.

 

However, the opportunity to open a mini-NT is much less frequent, as it is far more likely that there will be an opening bid of some sort in front of the hand holding the mini-NT opener.

 

When one holds a traditional strong 1NT opening hand, the chances of someone else opening the bidding in front of your hand is much less.

 

Furthermore, the vast majority of players who play a mini-NT do so only in 1st and 2nd positions, for obvious reasons.

 

So, if one were to compare the number of times a mini-NT hand comes up when that hand actually has the opportunity to open a mini-NT vs. the times that a strong 1NT opening comes up and that hand has the opportunity to open a strong 1NT, I suspect that you will find the numbers to be much closer to equal than you would have originally thought.

Anyone out there willing to generate a sim (won't be home til quite late tonight)

 

I'd be interested in seeing

 

The PDF for HCPs given a first seat opening

The PDF for HCPs in second seat, conditional on a first seat pass

The PDF for HCPs in third seat, conditional on a first/second seat pass

The PDF for HCPs in 4th seat, conditional on three passes

[Cascade]

"B. Special Partnership Understandings

1. (a) In its discretion the Regulating Authority may designate certain

partnership understandings as “special partnership understandings”. A

special partnership understanding is one whose meaning, in the opinion of

the Regulating Authority, may not be readily understood and anticipated by

a significant number of players in the tournament.

So, what ACBL needs to do in order to regulate a NT opening which may commonly be made with a singleton is to designate it as a special partnership understanding.

 

Or, they could just make a blanket proclamation that calls that are not natural by their definition of natural are special partnership understandings.

No that would be unreasonable because then:

 

They would be overriding the requirement that these Special Partnership Understandings require '...not be readily understood or anticipated...in the tournament'.

 

This could easily very from tournament to tournament.

 

I doubt that one could claim that 9-12 1NT is not able to be readily understood. And further if I pre-alert or it is known that some play this method then it would be hard to reasonably claim that this method could not be anticipated.

 

The only reason it is not anticipated is because it has been made illegal.

[jdonn]

I disagree with your interpretation of 'anticipated'. By your definition any system or bid at all is anticipated as long as you tell your opponents before play begins. In other words, the word would be meaningless in that context. No, the only reasonable interpretation is that it means anticipated in advance. And it is more than reasonable (quite certainly true in many jurisdictions in fact) for an organization to believe that frequent notrump openings with a singleton "may not be readily anticipated by a significant number of players" in many tournaments.

[awm]

Suppose partner and I just agreed to open 1NT on all hands in the 10-12 hcp range. It's easy to explain, we're happy to disclose it... and it's not forcing at all and conveys a willingness to play in notrump. After all, notrump could be right on any hand.

 

Yet I think it's reasonable to say that this is a pretty "weird" method, not "natural" at all and potentially could be restricted.

 

The question is just where you draw the line. ACBL has decided that two doubletons is okay, but singleton is not. This seems a reasonable enough place to me.

 

Of course, you can always bid whatever you want on a particular hand. So there needs to be some guideline as to how frequent a "deviation from agreements" can be before it's not really a deviation any more. This is where the much maligned "1%" rule comes from. Again, you can argue about where the line should be, but it seems logical that if I very often bid in a way which contradicts my disclosed agreements, I'm not really disclosing my agreements accurately and there should be some consequences. And if the way I actually bid implies an illegal agreement, then there should be serious consequences.

[Cascade]

The question is just where you draw the line. ACBL has decided that two doubletons is okay, but singleton is not. This seems a reasonable enough place to me.

On what basis is this reasonable?

 

A 1NT opening with an occasional singleton (our frequeny might be up as high as 10% 4-4-4-1 with black singletons, other 4-4-4-1 with singleton high honours, 5-4-3-1 with singleton high honours but with some exceptions, maybe occasional other hands) requires no special defense. In most cases we cannot find out about the singleton (unless it occurs by accident as a cue-bid or something). The exception is that we can bid 3♣ 1=4=4=4 and 3♦ 4=4=4=1 to show maximums with usually a small singleton in response to Stayman.

 

Essentially these are natural bids we are indicating a desire to play in notrumps unless partner has sufficient distribution to warrant another contract or unless we find a fit in some suit.

 

The affect of the regulation is that for example a 4=4=4=1 hand in a five-card major system we must open 1♦ and then over a 2♣ response we have to make some silly bid - rebid our diamonds, reverse into a major with insufficient strength or distribution (depending on the no trump range) or ironically rebid no trumps which apparently is fine and dandy with a singleton as a rebid when it is not suitable as an opening.

[awm]

Cascade's argument here sounds an awful lot like:

 

"This is a method I want to play therefore it is ridiculous to regulate it."

 

to me. Why is this "a natural bid"? It doesn't seem natural to me (and it doesn't fall under any definition of natural I've ever seen, including ACBL's or WBF's). Why is bidding your four card suits consecutively ridiculous but opening 1NT with a small singleton not ridiculous? Why is this easy to defend (certainly it is very likely to cause opponents to go wrong in play or defense)? If 1444 1NT openings are okay because of rebid problems, why not 0445?

 

Honestly this sounds an awful lot like the reasoning people used to argue that 1♣ "clubs or balanced" was a natural bid and that artificial defenses should be BSC. Back when that came up, I thought it was a terrible argument and so did Cascade. I'm disappointed to see that his opinions are so heavily influenced by what he personally wants to play or thinks of as good bridge.

[Cascade]

Cascade's argument here sounds an awful lot like:

 

"This is a method I want to play therefore it is ridiculous to regulate it."

 

to me. Why is this "a natural bid"? It doesn't seem natural to me (and it doesn't fall under any definition of natural I've ever seen, including ACBL's or WBF's). Why is bidding your four card suits consecutively ridiculous but opening 1NT with a small singleton not ridiculous? Why is this easy to defend (certainly it is very likely to cause opponents to go wrong in play or defense)? If 1444 1NT openings are okay because of rebid problems, why not 0445?

 

Honestly this sounds an awful lot like the reasoning people used to argue that 1♣ "clubs or balanced" was a natural bid and that artificial defenses should be BSC. Back when that came up, I thought it was a terrible argument and so did Cascade. I'm disappointed to see that his opinions are so heavily influenced by what he personally wants to play or thinks of as good bridge.

You can think it sounds like that if you want?

 

I was trying to explain and to get some information about why you think this is the right place to draw the line.

 

I don't think you are correct about the WBF definition. Their definition is "Natural a call or play that is not a convention (as defined in the Laws)". Although this does not appear to have been updated since the law changes maybe if I look under specific tournaments there maybe an update. Essentially as far as 1NT is concerned conventional would be showing something other than willingness to play in no trumps.

 

Consequently my WBF system card is marked as "GREEN - natural" and we have never had a problem over that classification.

 

It does seem weird to me something that is WBF GREEN is unplayable in North America.

[Cascade]

I don't agree with your premise.

 

It is no doubt true that hands meeting the requirements for opening a mini-NT are more common than hands meeting the requirements for opening a traditional strong 1NT.

 

However, the opportunity to open a mini-NT is much less frequent, as it is far more likely that there will be an opening bid of some sort in front of the hand holding the mini-NT opener.

 

When one holds a traditional strong 1NT opening hand, the chances of someone else opening the bidding in front of your hand is much less.

 

Furthermore, the vast majority of players who play a mini-NT do so only in 1st and 2nd positions, for obvious reasons.

 

So, if one were to compare the number of times a mini-NT hand comes up when that hand actually has the opportunity to open a mini-NT vs. the times that a strong 1NT opening comes up and that hand has the opportunity to open a strong 1NT, I suspect that you will find the numbers to be much closer to equal than you would have originally thought.

Anyone out there willing to generate a sim (won't be home til quite late tonight)

 

I'd be interested in seeing

 

The PDF for HCPs given a first seat opening

The PDF for HCPs in second seat, conditional on a first seat pass

The PDF for HCPs in third seat, conditional on a first/second seat pass

The PDF for HCPs in 4th seat, conditional on three passes

HCP      1st seat        2nd seat        3rd seat        4th seat      
       0.44128108      0.2963114       0.17652121      0.08588631      
0       0.00365543      0.00172555      0.00036523      0      
1       0.00787954      0.00410852      0.00106063      0      
2       0.01358222      0.00772989      0.00238525      0      
3       0.02462392      0.01521253      0.00551263      0      
4       0.03847942      0.02560515      0.01079534      0      
5       0.05183734      0.03730851      0.01818958      0      
6       0.06551482      0.05059979      0.02830066      0      
7       0.08026772      0.06634884      0.04221567      0.00053485      
8       0.08894528      0.07845606      0.05632383      0.00349696      
9       0.09354203      0.08787038      0.07065839      0.01182899      
10      0.09405601      0.09376693      0.08392605      0.02804543      0.086512794
11      0.08942656      0.09436475      0.09342423      0.05166522      0.088352293
12      0.08025309      0.08943982      0.0971405       0.07782625      0.085747777
13      0.06914234      0.08109073      0.09591242      0.10181306      
14      0.05693845      0.07005879      0.08980479      0.11855111      
15      0.04424069      0.05697499      0.07855836      0.1232084       0.06085405
16      0.03313078      0.04450563      0.06553666      0.11793912      0.049505478
17      0.02363095      0.03302106      0.05166343      0.10389384      0.038255157
18      0.01604201      0.02327522      0.03840841      0.08456908      
19      0.01036278      0.01554094      0.02686502      0.06359527      
20      0.00644364      0.00996626      0.01794193      0.04498471      
21      0.00378244      0.00601313      0.01122105      0.02947541      
22      0.00209297      0.00340836      0.00657576      0.01795874      
23      0.00111366      0.00186594      0.00367143      0.01029791      
24      0.00055871      0.00094897      0.00190503      0.00548811      
25      0.00026269      0.00045504      0.00093035      0.002721      
26      0.00011735      0.00020293      0.00042178      0.00124688      
27      0.00004946      0.00008569      0.00018026      0.00054215      
28      0.00001831      0.00003241      0.00006886      0.00020692      
29      0.00000639      0.00001169      0.00002512      0.00007611      
30      0.00000213      0.00000393      0.00000823      0.00002557
31      0.0000006       0.00000116      0.00000229      0.00000671
32      0.00000024      0.00000031      0.00000061      0.00000173
33      0.00000003      0.00000007      0.00000019      0.00000034
34      0               0.00000003      0.00000003      0.00000013
35      0               0               0               0
36      0               0               0               0
37      0               0               0               0

 

Based on 100 000 000 hands in each column.

 

The first row is a separate simulation counting the number of times there was an opening in each seat.

 

Its not completely ideal but I based the opening or not opening decision on the following:

 

Open all 12 HCP

 

Open all 11 HCP with a five-card suit

 

Open all 10 HCP with a six-card suit or two five-card suits

 

Open all 6-9 with six spades, hearts or diamonds

 

Open all 6-9 with seven cards in any suit

 

The last column shows the relative frequencies of 10, 11, 12, 15, 16 and 17 HCP over all positions.

[Mbodell]

Of course you are technically correct, I didn't mean to be the first to gloss over this point. However, 3 times in one session is so unlikely if you don't generally open 1NT with a singleton with enough frequency to alert it that I don't think you will be wrong once in ten lifetimes if you force such a partnership to alert / change their methods / whatever.

I'm not sure about the relative frequencies.

 

Mini NTs are much more common than strong NT openings. This might be enough to push things into the realm of the plausible.

I agree with your assessment that mini-nt are much more common than strong nt. Also, adding an extra point in is much, much more common too. I've played a 12-15 range and it comes up all the time, way more often than a 15-17. And I often play a 10-12 or 12-14 depending on seat and vulnerability and we bid 1nt way more commonly than I bid 1nt in my 15-17 partnerships.

 

If your range is 10-13 like OP, and you open balanced and semi-balanced hands nt, I think you'd find a very large percentage of your first seat auctions start with 1nt. Not as many as pass, which is like 50%, but probably something in the range of 15-20%.

[the hog]

Well I do.  I don't think they should be in the business of legislating what constitutes "good bridge".  If people get good results from opening 1nt with small singletons, they ought to be able to do so IMO.  It's a natural NF bid!  Nor should they be prevented from getting the bad results.  People should have the right to be crazy, as long as they disclose.

Every argument you've made here would seem to apply equally well to a 2♥ opening showing a weak two in either major. Some people think this method is "good bridge" and as long as they disclose, why shouldn't they have the right to be crazy? The bid's even "natural" in the sense that partner will often pass it and it expresses a willingness to play 2♥ opposite a (semi)-balanced hand without much in the way of values.

 

Of course, if you agree that 2♥ showing a weak two in either major should be allowed in all events and that ACBL (or WBF for that matter) shouldn't be in the business of legislating whether this convention constitutes "good bridge" then you're entitled to your opinion -- but you should recognize that this opinion differs from that of the vast majority of bridge players.

Really Adam? Can you please prove this claim? If not, why make it? Are you aware that some of the world's best players used this opening?

[hrothgar]

Based on 100 000 000 hands in each column.

 

The first row is a separate simulation counting the number of times there was an opening in each seat.

 

Its not completely ideal but I based the opening or not opening decision on the following:

 

Open all 12 HCP

 

Open all 11 HCP with a five-card suit

 

Open all 10 HCP with a six-card suit or two five-card suits

 

Open all 6-9 with six spades, hearts or diamonds

 

Open all 6-9 with seven cards in any suit

 

The last column shows the relative frequencies of 10, 11, 12, 15, 16 and 17 HCP over all positions.

Thanks Wayne

 

Just to make sure I'm reading things right, it looks as if the ratio of

 

Frequency of a 10-12 NT opening : Frequency of a 15-17 NT opening is ~ 26 : 15

 

From the looks of things, one could achieve an even higher frequency if you chose

 

10 - 12 in seats 1-3 and then switched to 14-16

[Cascade]

Based on 100 000 000 hands in each column.

 

The first row is a separate simulation counting the number of times there was an opening in each seat.

 

Its not completely ideal but I based the opening or not opening decision on the following:

 

Open all 12 HCP

 

Open all 11 HCP with a five-card suit

 

Open all 10 HCP with a six-card suit or two five-card suits

 

Open all 6-9 with six spades, hearts or diamonds

 

Open all 6-9 with seven cards in any suit

 

The last column shows the relative frequencies of 10, 11, 12, 15, 16 and 17 HCP over all positions.

Thanks Wayne

 

Just to make sure I'm reading things right, it looks as if the ratio of

 

Frequency of a 10-12 NT opening : Frequency of a 15-17 NT opening is ~ 26 : 15

 

From the looks of things, one could achieve an even higher freqeuncy if you chose

 

10 - 12 in seats 1-3 and then switched to 14-16

Yes.

 

The numbers would be slightly different since i would have to redo the simulation for opening all 10-11 Balanced.

[ArtK78]

The simulation shows what we all knew to be the case: Balanced hands with 10-12 HCP are far more common than balanced hands with 15-17 HCP.

 

That is not the point.

 

My point is that one will not be given the opportunity to open a 10-12 HCP 1NT opening as often as one will be given the opportunity to open a 15-17 HCP 1NT opening due to:

 

(1) An opening bid by an opponent prior to the first opportunity to bid for the balanced 10-12 HCP hand.

 

(2) An opening bid by partner prior to the first opportunity to bid for the balanced 10-12 HCP hand.

 

(3) System restrictions which prohibit opening a 10-12 HCP 1NT in third or fourth seat.

 

(4) System restrictions which prohibit opening a 10-12 HCP 1NT vulnerable.

 

It is also possible that points #1 and #2 apply to a 15-17 HCP 1NT opening, but, given that there are fewer HCPs available for the other three hands when one holds a balanced 15-17 HCP hand, the possibility of a prior opening bid is diminished.

 

As to point #3, I play a 10-12 HCP 1NT opening nonvulnerable in 1st and 2nd seat in the context of a light opening system (all 10 counts are opened). Partner's pass in 1st or 2nd seat would deny 10 HCP, so it would be suicidal to open a 10-12 HCP 1NT in 3rd of 4th seat. Consequently, we play 15-17 HCP 1NT openings in 3rd or 4th seat (and all seats vulnerable). I have made an argument to my partner that our 3rd and 4th seat 1NT openings should be 16-18 HCP, but he has not accepted my argument.

 

Given all of my restrictions, I find that a 10-12 HCP 1NT opening is LESS frequent than a 15-17 HCP 1NT opening.

[hrothgar]

The simulation shows what we all knew to be the case: Balanced hands with 10-12 HCP are far more common than balanced hands with 15-17 HCP.

 

That is not the point.

 

My point is that one will not be given the opportunity to open a 10-12 HCP 1NT opening as often as one will be given the opportunity to open a 15-17 HCP 1NT opening due to:

 

(1) An opening bid by an opponent prior to the first opportunity to bid for the balanced 10-12 HCP hand.

 

(2) An opening bid by partner prior to the first opportunity to bid for the balanced 10-12 HCP hand.

 

(3) System restrictions which prohibit opening a 10-12 HCP 1NT in third or fourth seat.

 

(4) System restrictions which prohibit opening a 10-12 HCP 1NT vulnerable.

 

It is also possible that points #1 and #2 apply to a 15-17 HCP 1NT opening, but, given that there are fewer HCPs available for the other three hands when one holds a balanced 15-17 HCP hand, the possibility of a prior opening bid is diminished.

 

As to point #3, I play a 10-12 HCP 1NT opening nonvulnerable in 1st and 2nd seat in the context of a light opening system (all 10 counts are opened). Partner's pass in 1st or 2nd seat would deny 10 HCP, so it would be suicidal to open a 10-12 HCP 1NT in 3rd of 4th seat. Consequently, we play 15-17 HCP 1NT openings in 3rd or 4th seat (and all seats vulnerable). I have made an argument to my partner that our 3rd and 4th seat 1NT openings should be 16-18 HCP, but he has not accepted my argument.

 

Given all of my restrictions, I find that a 10-12 HCP 1NT opening is LESS frequent than a 15-17 HCP 1NT opening.

Please go back and review how the simulation was constructed.

 

Wayne's simulation didn't assume the use of a 10-12 HCP 1NT opening. (It used a slightly more conservative opening style). However, I doubt that this would change the results that much.

 

Indeed, I'd bet dollars to donuts that a system using a 15 - 17 HCP 1NT opening in all four seats will have (significantly) fewer 1NT opening than one that uses a 10-12 HCP 1NT opening in all four seats. Your claim Cthat people shouldn't open a 10-12 NT in 4th seat therefore these frequencies shouldn't be excluded seems like apples to oranges comparison.

 

For what its worth, I agree that a system that uses a 10-12 HCP 1NT opening in all four seats will open 1NT less frequently than one that opens

 

10-12 in first / second

11-13 in third

14 - 16 in fourth

 

Let's go back to the original discussion:

 

If you prefer, we can modify my original argument as follows:

 

Rather than looking at a system than uses a 10-12 HCP 1NT opening in all four seats, lets look at a system designed to maximize the frequency of a 1NT opening all four seats.

 

Contrast the freqency of said NT opening with that of a 15 -17 HCP 1NT opening...

[ArtK78]

My primary point is that someone else is likely to open in front of a 10-12 1NT opener more often than someone else is likely to open in front of a 15-17 1NT opener, limiting the opportunity to open a 10-12 1NT.

[rbforster]

As to point #3, I play a 10-12 HCP 1NT opening nonvulnerable in 1st and 2nd seat in the context of a light opening system (all 10 counts are opened).  Partner's pass in 1st or 2nd seat would deny 10 HCP, so it would be suicidal to open a 10-12 HCP 1NT in 3rd [or 4th] seat. 

I'm not dead yet!

 

I play a very similar opening style, but we open a 10-12 NT in 3rd seat (although not 4th for constructive reasons). Admittedly this is only when we're NV, but it's not an obviously bad thing.

[hrothgar]

My primary point is that someone else is likely to open in front of a 10-12 1NT opener more often than someone else is likely to open in front of a 15-17 1NT opener, limiting the opportunity to open a 10-12 1NT.

 

Wayne, any chance you could rerun the simulation to address this?