Presumptive Fit Preempts .. Jammer 2D

[BridgeBuff]

There is a considerably shorter version of this article

 

http://www.bridgebuff.com/jammer2d.htm

 

sitting in Jeff Ruben's desk at the Bridge World awaiting publication.

 

Meanwhile, any comments would be appreciated. The Jammer 2♦ bid is a modest preempt in some suit, but you have to scramble to identify the suit. It is allowed in most ACBL events because it has an anchor suit (♠). Pard and I have used it with considerable success in (strong) club games, but the pre-alert requirement finally pissed me off and we stopped using it. I should dredge it back out for some team games ...

 

As we used it, 2♦ showed a 5431 or 4432 or 4441 or 5440 pattern (90% of suitable hands include a 3-bagger) including 4 or 5 spades (80% of the time = 4) and we used a 5-10 HCP range, partly because the club insisted we couldn't go lower. Typical openers would be xxxx/AQx/x/Jxxxx and Kxxx/QJxx/Kx/xxx and true three-suiters like QJxxx/Kxxx/-/Qxxx.

 

The bid was very destructive, came up once or twice a session, generated good results, and was a lot of fun. It is also relatively safe ... findable fits are lawful nearly two-thirds of the time.

[hrothgar]

Comment the first: Good luck ever playing this in the ACBL. Current ACBL systems regulations define assumed fit methods as inherently destructive. [Please note: using expressions like "Destructive" to describe your own methods is very bad for those of us who wish to play assumed fit methods in the US]

 

Comment the second: I consider the bid interesting, but i think that it is weaker than the Frelling 2D opening that I use. The Jammer 2D opening is (essentially) forcing, which makes defense much easier. Furthermore, the opponents have a known cuebid at the 2 level.

 

Comment the third: Personally, I would prefer less "filler", with a greater focus on the constructive response structure.

[BridgeBuff]

Well thanks for the comments Hothgar. I guess.

 

Comment the one. It is playable in the ACBL because of the anchor suit. Or at least I haven't been stopped using it in club games (which are very conservative). Perhaps you thought that was filler and missed it.

 

Comment the two. I'm real sure the ACBL isn't vetting this forum for the 'destructive' word, so if I were you, I'd rest easy and stop fretting.

 

Comment the three. The bid wasn't intended as a full two-suit system, more as something interesting and fun to do with the 2♦ spot. I googled Frelling, it looks interesting and I'm happy for you that you like that system. I'd just rather do something else with my 2♥ and 2♠ spots.

[TimG]

The Jammer 2♦ bid is a modest preempt in some suit, but you have to scramble to identify the suit. It is allowed in most ACBL events because it has an anchor suit (♠).

 

As we used it, 2♦ showed a 5431 or 4432 or 4441 or 5440 pattern (90% of suitable hands include a 3-bagger) including 4 or 5 spades (80% of the time = 4) and we used a 5-10 HCP range, partly because the club insisted we couldn't go lower.

The ACBL has banned this type of method when it can be made on hands with 44 in the long suits. If you wanted to play it these days, you'd have toeliminate the 4432 hands.

 

Also, it would be a mid-chart method and would require an approved defense. With an anchor suit of spades and a requirement of at least 54, you should be able to get a defense approved. But, given my interactions with the C&C Committee, I would bet against it.

 

Tim

[BridgeBuff]

TimG:

 

Thanks. I provided a defence of course when I pre-alerted. Apparently the prohibition against 4=4 lengths hasn't filtered down to the club level here in Toronto. I seem to recall that I also played it in a local Regional ... but might be thinking of some other toy.

[hrothgar]

Well thanks for the comments Hothgar. I guess.

 

Comment the one. It is playable in the ACBL because of the anchor suit. Or at least I haven't been stopped using it in club games (which are very conservative). Perhaps you thought that was filler and missed it.

 

Comment the two. I'm real sure the ACBL isn't vetting this forum for the 'destructive' word, so if I were you, I'd rest easy and stop fretting.

 

Comment the three. The bid wasn't intended as a full two-suit system, more as something interesting and fun to do with the 2♦ spot. I googled Frelling, it looks interesting and I'm happy for you that you like that system. I'd just rather do something else with my 2♥ and 2♠ spots.

The ACBL explictly bans assumed fit methods that could be based on 4432 shape. Even in the absence of this regulation, you need to get a suggested defense approved by the Conventions Committee.

 

I wish you luck...

[TimG]

TimG:

 

Thanks. I provided a defence of course when I pre-alerted. Apparently the prohibition against 4=4 lengths hasn't filtered down to the club level here in Toronto. I seem to recall that I also played it in a local Regional ... but might be thinking of some other toy.

Clubs are actually allowed to do just about whatever they want with regard to conventions. They can be more or less liberal than ACBL tournaments, and don't have to follow any particular convention chart.

 

The 4-4 prohibition is relatively new -- my guess is it was passed at the Long Beach NABC in the summer of 2003.

 

The requirement for suggested defense to first be approved by the C&C Committee is about 3-4 years old.

[BridgeBuff]

Hey JimG

 

What effect does that 4=4 prohibition have on a Roman 2♦ opener, which can be on 4441? Or is that exempted for some reason? That was part of my sale to the clubs ... 'hey this is just a micro-roman opener with a generous definition of 3-suiter'.

[hrothgar]

Hey JimG

 

What effect does that 4=4 prohibition have on a Roman 2♦ opener, which can be on 4441? Or is that exempted for some reason? That was part of my sale to the clubs ... 'hey this is just a micro-roman opener with a generous definition of 3-suiter'.

Min-Roman is constructive, Jammer 2♦ is preemptive...

any clubs are MUCh more permissive than the ACBL.

[TimG]

Hey JimG

 

What effect does that 4=4 prohibition have on a Roman 2♦ opener, which can be on 4441? Or is that exempted for some reason? That was part of my sale to the clubs ... 'hey this is just a micro-roman opener with a generous definition of 3-suiter'.

The 44 prohibition applies to weak openings.

[TimG]

This is the interesting stuff, IMO:

 

How does the lawfulness of these openings compare to other shape-showing bids? Here are a few, listed in decreasing lawfulness of the bid. The ‘frequency’ guesstimate is necessarily crude, because style will be a large factor The frequency for the non-openers assumes the appropriate opening has already been made ... that is, for two heart Michaels, given that opener has opened one spade, intervenor will have the ingredients for a Michaels bid maybe 3% of the time.

 

I have one question, though. When you did the ACBD calculations for a 2H Michaels bid, did you assign opener 5+ hearts as part of the constraints? That will, obviously, have an effect on how often the intervening side has a fit. And, I'm not able to intuit whether it was considered of not.

 

Tim

[mikestar]

Given a venue where you can actually play it, perhaps the best variation would be long diamond Jammer. Now it can be passed quite often and defenses that involve passing some good hands and doubling later (fairly playable against long spade Jammer) become untenable.

[BridgeBuff]

Mikestar:

 

That's a good point about defencing it. Long-diamond loses some preemptive value but is tougher to defend. If I find a venue I'll need about a year with both .. :-)

 

Actually I have any number of local venues where I can play it ...

 

TimG:

 

Yes all the simulations were done with a deal generator, so the ABCD values reflect 'true' around-the-table patterns, and sensible, but not double-dummy, decisions by responder. For example, responder with 3=3=5=2 pattern would bid 2♠ to end in his [probable] 4=3 fit, alas missing his dandy 5=5 diamond fit when opener was 4=3=5=1. 5332 in responder is the 'difficult' shape.

[Free]

Given a venue where you can actually play it, perhaps the best variation would be long diamond Jammer. Now it can be passed quite often and defenses that involve passing some good hands and doubling later (fairly playable against long spade Jammer) become untenable.

Lol, you can play it anywhere in the world except ACBL land... So I think Jammer is a nice tool :) Just not as nice as Frelling-2 :D

[jtfanclub]

I am somewhat confused. When discussing the frequency, 4432 is mentioned a lot, and in fact it's considerably more likely than all of the other shapes combined. But when you discuss the play of it, it seems to vanish.

 

I think if the system required an exact 4432 pattern, it would clearly be a bad system- you'd often end up in a nice 4-4 fit at the 3 level with about 16-18 hcp and no shape, something like:

 

[hv=w=saxxxhxxdaxxcxxxx&e=sxxhxxxdkxxxcakxx]266|100|[/hv]

 

And 4-4 is one of the better hopes- you could be 4-3. Somebody smarter than me can figure out the LAW on the odds of a 16+ total fit when you know one hand is 4432, but I daresay that lowers the chances considerably.

 

So you take out the 4432. Now it seems like a good bid- but you've just dropped the frequency to barely a third of its previous level. So one of your main arguments is lost.

 

I'm obviously missing something- care to enlighten me?

[Free]

Bidding with 4432's gets you at 2-level in the "right" contract. With the hands you gave, nobody would open as 4432 with a bid above 2♣. Bidding 4432's is similar to DONT. You make sure you can play at 2-level in any 4-card suit opener has. Otherwise you're just playing a poor convention imo.

 

Just take a look at frelling two's:

2♦ shows at least 4-4 in ♦ and a Major. 2♦ and 2M can be played

2♥ shows at least 4 ♥s, and 4+♠/5+♣. You can play 2M (4 card suits), and when you have to play at 3-level, opener has at least a 5 card.

2♠ I don't like, but the concept is similar: you need 5+♣ when you have a 2-suiter.

 

Consider DOPTO (Belgian 'invention'):

2♣, 2♦ and 2♥ show at least 4-4 in the bid suit and a higher suit. This means with 4432's, you'll open the lowest, and you can end up playing in a 4-4 or 4-3 at 2-level, which is both acceptable.

[jtfanclub]

Bidding with 4432's gets you at 2-level in the "right" contract. With the hands you gave, nobody would open as 4432 with a bid above 2♣. Bidding 4432's is similar to DONT. You make sure you can play at 2-level in any 4-card suit opener has. Otherwise you're just playing a poor convention imo.

 

Just take a look at frelling two's:

2♦ shows at least 4-4 in ♦ and a Major. 2♦ and 2M can be played

2♥ shows at least 4 ♥s, and 4+♠/5+♣. You can play 2M (4 card suits), and when you have to play at 3-level, opener has at least a 5 card.

2♠ I don't like, but the concept is similar: you need 5+♣ when you have a 2-suiter.

 

Consider DOPTO (Belgian 'invention'):

2♣, 2♦ and 2♥ show at least 4-4 in the bid suit and a higher suit. This means with 4432's, you'll open the lowest, and you can end up playing in a 4-4 or 4-3 at 2-level, which is both acceptable.

Both of what you said make a lot of sense to me. However, if a Jammer 2D is opened with 4 spades and 4 clubs, you're already too high for clubs, right?

 

So instead Jammer promising 4+ spades, why not have it promise, say 3+ cards in all suits besides clubs and not 4-3-3-3 with 4 clubs? Now you've actually increased the frequency, and it serves the purpose you just mentioned.

[BridgeBuff]

I don't have the precise percentages in front of me, but 5431 (with 4 or 5 spades) was about 45% of suitable hands, 4432 (with 4 spades) about another 45%, and true three suiters 4441 and 5440, again with 4 or 5 spades, were about 10% in total.

 

If you played a 5 to 10 HCP range, about 7% of your holdings would qualify for the 2♦ opening if 4432 hands were included, and if not, what, about 4% or so.

 

Still useful.

[BridgeBuff]

Both of what you said make a lot of sense to me. However, if a Jammer 2D is opened with 4 spades and 4 clubs, you're already too high for clubs, right?

 

That hand is awkward. But any system produces lousy results sometimes. When partner bids an Unusual NT, I'm always 5=5 in the majors. Overall it produces a lawful fit nearly 2/3 of the time (and the opps have no way of knowing if you are in a predicament or not).

 

Actually I think the worst possible responder holding is 2335, when his best chance for a decent spot is to bid 2♥ and opener will pass with three of them, gulp. This problem doesn't go away if you remove 4432 hands, opener could still be 4351.

 

Pesonally I don't like using up three two-level bids like the Frelling trio does.

[jtfanclub]

Both of what you said make a lot of sense to me. However, if a Jammer 2D is opened with 4 spades and 4 clubs, you're already too high for clubs, right?

 

That hand is awkward.

But the question I have is, if it's akward, why include it? It seems like your system would work better with 4333 spades than 4324 spades/clubs.

 

Am I wrong?

[hrothgar]

Personally I don't like using up three two-level bids like the Frelling trio does.

I'd LOVE to be able to compress the Frelling 2 structure into a smaller number of openings, or, alternatively to increase the number of hand types shown with one or more of the openings. I even experimented with bundling a hand with 5+ Diamonds and 5+ Clubs into the 2D opening bid. However, I don't see anyway to do so while preserving anything resembling a constructive response structure.

 

I'm quite proud of the fact that the Frelling 2 opening structure allows very frequent openings while preserving the option for accurate game explorations.

 

Its possible that the Jammer 2D allows a better response structure than Frelling. In particular, if you can use 2H as an artifical ask rather than a scramble, I can almost see things working. As I noted before, I'd be very interested in seeing your recommended response structure...

[Flame]

Frelling seems like a great convention, i already asked my partner to play it and hopefully he will agree.

I have some questions

1. on bad vul maybe even when everyone is vul, doesnt it make sense to make it 5/4 instead of 4/4 ?

2. Will the 2d opening lead to many bad mp results because we will play partscores in diamonds instead of major ?

3. does the system as published in Chris Ryall's site was updated or is it the one you play ?

Thxs for sharing this cool tool.

[hrothgar]

Frelling seems like a great convention, i already asked my partner to play it and hopefully he will agree.

I have some questions

1. on bad vul maybe even when everyone is vul, doesnt it make sense to make it 5/4 instead of 4/4 ?

2. Will the 2d opening lead to many bad mp results because we will play partscores in diamonds instead of major ?

3. does the system as published in Chris Ryall's site was updated or is it the one you play ?

Thxs for sharing this cool tool.

The version that was posted on Chris Ryall's web site is still pretty accurate. I'm sure that there are some typos (I'm notorious for typos), but no major changes to the structures.

 

There is one point that I think requires more emphasis. Over time, I've noticed that responder should bid very conservatively holding balanced hands. For example, suppose that partner opens 2♦ and you hold

 

♠ K7

♥ KQT3

♦ AQ3

♣ T864

 

You have a nice 14 count. If partner holds a shapely unbalanced hand with hearts, 4♥ could easily be on. If partner has a nice maximum, you could even make 3N. Personally, I'd pass. I find that the games that I miss are more than balanced by the chance to defend doubled contracts after over aggressive balancing decisions by the opponents.

 

Please note: Change the hand slightly such that responder holds:

 

♠ K7

♥ KQT3

♦ AQT3

♣ 864

 

And I would recommend a 3♣ response. here, I am happy to declar 3♦ opposite Diamonds and Spades and will get to 4♥ opposite a maximum with the red suits.

 

To date, I haven't required 5-4 shape to amke a vulnerable 2♦ opening. if you do decide to do so, you'l realize more benefits if you require 5 cards in a known suit.

[BridgeBuff]

Jtfanclub:

 

Of course there are combinations of patterns that don’t do well. It is that way with any bid. I don’t stop using Unusual NT because sometimes partner is 5=5 in the majors. I don’t stop opening 1H because sometimes LHO has eight of them. The bid is lawful about 2/3 of the time, and not lawful about 1/3. You found one of the 1/3. This Jammer is way less risky than opening 3♣ with a 6-bagger.

 

And no, using 4=3=3=3 doesn’t work because there are too many bad matches.

 

You would be making the same point about diamonds if opener had 4=2=4=3 instead of 4=2=3=4 shape. You have to consider where it works, not just where it doesn’t. I agree it is possible that removing 4432 might improve the lawfulness (with lower frequency) and I’ll look at that down the road. But there IS an advantage to those 4432 hands … dummy doesn’t go down with a singleton or void in partner’s 6-bagger.

 

There are other variations that are more lawful. Jammer Short Club, for example, is very safe ….

 

Hrothgar:

 

Simple response system. This unlikely is optimum; some smart guy can sharpen it up. Remember there is a ‘safe haven’ in the anchor suit spades.

 

2♥ is pass/correct (opener passes even with three hearts)

2♠ says pass

2NT says bid best minor (also after 2♦/2♥||2♠/2NT)

3♣ says pass

3♦ is artificial force

3♥ is good suit

3♠ is preemptive

 

Responder needs a forcing bid; looks to me like 3♦ is best. 2NT either directly or as a second bid asks for best minor.

 

Responder has a one-suiter (6+). With long diamonds he passes. With hearts he bids 2♥ and if opener rebids 2♠ (denying three hearts) then must decide what to do. If including 4432, then much of the time opener will have a doubleton heart so 3♥ is an option. Or responder can bid 2♠ with three, or trot out a 4-card minor. With 2=6=3=3 he, what, can rebid 3♥ or try 2NT. I would have to test that scenario to determine which was best long-term strategy. With 6+ clubs he bids 3♣ and hopes.

 

If he has 4+ spades he bids spades.

 

If responder has a “two-suiter” 4=4 or better, he usually bids the cheaper suit. With 3=4=4=2 he tries 2♥ (slightly better than 2♠) and passes 2♠. With 2=4=3=4 or 2=4=4=3 he tries 2♥, then after 2♠ bids (I can’t remember if 2NT is better than simply bidding the four-bagger, have to look it up). With 2=4=5=2 or 2=4=2=5 he starts hearts, then bids the minor.

 

The worse responder holdings are 2=335 hands. With five diamonds, pass. With five hearts, try 2♥ then 2NT. With 2=3=3=5, try 2♥ and get stuck sometimes in your 3=3 heart fit (although opps have no idea of course).

 

There are some sample auctions here

 

http://www.bridgebuff.com/jammer2d.htm

[hrothgar]

Hrothgar:

 

Simple response system. This unlikely is optimum; some smart guy can sharpen it up. Remember there is a ‘safe haven’ in the anchor suit spades.

 

2♥ is pass/correct (opener passes even with three hearts)

2♠ says pass

2NT says bid best minor (also after 2♦/2♥||2♠/2NT)

3♣ says pass

3♦ is artificial force

3♥ is good suit

3♠ is preemptive

From my perspective, this illustrates the big problem with this opening.

 

By your own calculations, you're opening 2♦ on 15% of all hands, and from what I can tell you can't control the auction afterwards.

 

Case in point: How would you handle the following hand types:

 

Game invitational values with 4-5 Hearts?

Game forcing values with 5 Hearts?

Game forcing values with 3 Spades?

Game forcing hands with both minors?