Splinters and control bids

[Dinarius]

The reason I'm asking is that I like the unambiguous clarity of splinters and control bids showing *only* Aces and voids, and I hate the ambiguity introduced by also allowing singletons (usually as part of Splinters).

 

Simply put, short of a ruff or an over-ruff, an Ace or a void are cast-iron first round controls. A singleton isn't.

 

What do others think?

 

D.

[fromageGB]

I think you need to distinguish between "splinters" and "control bids". I would assume the former is a jump to show support for partner's suit, and the latter a forcing bid made after support has already been agreed, the control bid (or "cue" bid) being game forcing.

 

The control bid is usefully either Ace or void, or depending on your methods, any of A, K, void, singleton. This helps slam judgement.

 

The splinter should be singleton or void in my view, and never an Ace. If you have shortage your partner knows exactly how to revalue his hand, but if your splinter was an Ace, he has dramatically come to the wrong valuation. Well, the drama happens later, when you end in obviously the wrong contract.

 

Splinters that may be singleton or void happen more often than restricting it to just one of those (and if you did so restrict what would you do with the other hands?) , and ambiguity is not really a major problem. It certainly is potentially a problem if you go on to ask for for aces, so it is good to have a follow-up bid over the splinter to ask whether it is singleton or void, if you intend to perhaps later ask for aces. For my partnerships we use the next step to ask "singleton or void?" with a 2-step response, and because you can't do this with a splinter in the suit beneath trumps, we reserve that bid for singleton only, and employ a different bid somewhere (for us a 3NT reply) to show a void in the suit beneath trumps.

[Zelandakh]

What do others think?

For the most part it is not practical to distinguish between singletons and voids because there is not enough bidding space. In some auctions this is different though, most often those where 3NT is not needed as a natural call. For example over an opening 1♠ bid you can play:-

 

3NT = any void

... - 4♣ asks

... - ... - 4♦ = ♦ void

... - ... - 4♥ = ♥ void

... - ... - 4♠ = ♣ void

4♣♦♥ = singleton splinter

 

Or reverse it so that all singletons go through 3NT. Many expert pairs play schemes along these lines and it is certainly useful information.

 

There are a few additional possibilities too if this is important to you. A reasonably common question that comes up on BBF is what to do with a jump reverse (eg 1♦ - 1♠; 3♥). One of the possible options available is to use this sequence to differentiate between singleton and void splinters.

 

Unfortunately, many other auctions do not have 3NT or a convenient alternative call available for this purpose. In those cases you either have to live with the ambiguity or severely restrict the range of hands where you can use a splinter. My view is that the ambiguity is then the lesser evil.

[Vampyr]

Over major-suit openings, I can show voids, so splinters are always singletons; but we can do this only directly.

 

As far as control bids go, it is typical to bid first and second round controls below game; above game control bids are usually first round.

[Vampyr]

3NT = any void

... - 4♣ asks

... - ... - 4♦ = ♦ void

... - ... - 4♥ = ♥ void

... - ... - 4♠ = ♣ void

4♣♦♥ = singleton splinter

 

Similarly over 1♥, 3♠ can show a vomit LOL void, with 3NT as a spade splinter.

[sfi]

Autocomplete is not always your friend...

[Joe_Old]

A major plus for the splinter bid is that it helps partner evaluate his side suits for potential tricks. Partner can judge whether he has wasted values in your short suit (KQJxx isn't nearly as useful opposite a small singleton as opposite Axx), if a cross ruff will be a major source of tricks, etc. Therefore, the ambiguity of the splinter is usually outweighed by the picture it offers partner of how the two hands fit.

 

Limiting splinters to voids only is a huge loss. Since singletons are much more common than voids, you lose the ability to splinter on about two thirds of potential hands.

[Joe_Old]

Duplicate

[Left2Right]

What many do not realize is that one of the key purposes of shortness asking/showing bids is to diagnose duplication of value that may exist in the hand opposite the shortness. So whether it's Jacoby 2NT (asking) or a splinter (showing), adjusting the value of the other hand is crucial to knowing how to go forward in the auction.

 

Try my constraint file on this topic.

After you upload it, change the switch value: aStiffHonor = 1 to get only hands with a singleton ace or king.

 

Hand after hand, you'll see just how insidious it is to find honors in that suit on the other side of the table, which if transposed to some other suit make the hand much better.

 

Yes, this experience will prove that a singleton, even an ace, needs to be shown to allow partner to downgrade for duplication. And by the opposite token, when partner diagnoses that there is no duplication, you will have found one of those seeming miracle hands that fit perfectly.

[Lovera]

The reason I'm asking is that I like the unambiguous clarity of splinters and control bids showing *only* Aces and voids, and I hate the ambiguity introduced by also allowing singletons (usually as part of Splinters).

 

Simply put, short of a ruff or an over-ruff, an Ace or a void are cast-iron first round controls. A singleton isn't.

 

What do others think?

 

D.

That's right:a singleton is a control of second round, a void of first round. To clear you can reserve the third level only for splinter(=singleton) but in this case the "ambiguity" has to be solved, as it is, among the cue-bid answers.

[RD350LC]

A major plus for the splinter bid is that it helps partner evaluate his side suits for potential tricks. Partner can judge whether he has wasted values in your short suit (KQJxx isn't nearly as useful opposite a small singleton as opposite Axx), if a cross ruff will be a major source of tricks, etc. Therefore, the ambiguity of the splinter is usually outweighed by the picture it offers partner of how the two hands fit.

 

Limiting splinters to voids only is a huge loss. Since singletons are much more common than voids, you lose the ability to splinter on about two thirds of potential hands.

I agree here. Using a splinter to show a singleton is much more useful than using it to show a void.

[miamijd]

That sort of "unambiguity" isn't really what splinters and cue bids are designed for (and isn't needed).

 

First, splinters. When you jump the bidding, you need to show a very particular type of hand (a "picture bid" as it were). Otherwise, you are wasting valuable bidding space and not getting enough in return. That means splinters need to be limited to a pretty narrow range. I would say that if you are an ace better than a bare bones minimum is too strong.

 

Over 1S, I think:

 

Kxxx Axx x Qxxxx

 

is about the weakest splinter I can imagine. But if you make it:

 

Kxxx Axx x AQxxx

 

I think you are too strong to splinter originally (some would disagree). With that hand, I'd just bid 2NT (or whatever your 4-card game forcing raise is) and get a better idea of what my partner had.

 

The idea, of course, is to allow you to get to the "perfecto" slams when partner has something like:

 

AQxxxx x xxx AKx

 

Put that opposite hand one above and you have a cold 6S with 22 combined HCP. You'll never get there without the splinter.

 

You can also avoid exploring for bad slams when you have wastage:

 

AQJxxx xx KQJ Kx

 

This hand is better than the last one in terms of HCP, but it's much worse opposite a 4D splinter. If you know partner is minimum other than the splinter, you can safely sign off in 4S (which is probably all you can make).

 

Now for control bids. If you only like Aces and voids, I suspect you may be using cue bids to determine whether you have the necessary power for slam. That's generally not a good idea unless you're using them in conjunction with Serious/unserious 3NT and Last Train (see below). There are three things you need to determine when probing for slam:

 

1. Do we have the power?

2. Are we off two quick losers in a suit?

3. Are we off two quick high cards?

 

Cue bids help with #2. They allow you make sure you aren't off two quicks in a suit. So yes, second-round control is just as important as first-round control if what we're interested in is avoiding two fast ones.

 

Of course, Keycard BW or Kickback or whatever you use helps with #3.

 

For #1, there are a few good tools. One is to have bids that indicate your general strength once a fit is found. Most 4-fit GF bids (like Jacoby 2NT) have this feature. Another is to play two Meckwell-originated conventions I think are essential to good slam bidding:

 

Serious 3NT (or unserious 3NT if you prefer) (Eric gets the credit)

Last Train (to Clarksville) (Meck invented this one)

 

Serious 3NT allows you to make cue bids two different ways. You can say "I have a really strong hand" and then show controls or you can say "I don't have that good a hand -- you interested anyway?" and show controls.

 

Last Train allows you to check back one last time on hand strength before you commit to slam.

 

And both of them allow you to do all your cue-bidding below the game level -- where cue-bidding belongs.

 

I think Gitelman did a good series of articles about these conventions some time back.

 

Cheers,

mike

[Zelandakh]

But if you make it:

 

Kxxx Axx x AQxxx

 

I think you are too strong to splinter originally (some would disagree). With that hand, I'd just bid 2NT (or whatever your 4-card game forcing raise is) and get a better idea of what my partner had.

There is an excellent alternative to this - having 2 splinter ranges. If you are not worried about the singleton/void amibguity then you can use the structure I posted previously:-

 

1♠

==

3NT = maxi-splinter in any suit

... - 4♣ asks

... - ... - 4♦ = 0-1 diamonds

... - ... - 4♥ = 0-1 hearts

... - ... - 4♠ = 0-1 clubs

4♣♦♥ = normal splinter

==

 

A second alternative is to use an additional response to cover these hands, for example:-

 

1♠

==

3♥ = any maxi-splinter

... - 3♠ asks

... - ... - 3NT = any void

... - ... - ... - 4♣ asks

... - ... - ... - ... - 4♦ = ♦ void

... - ... - ... - ... - 4♥ = ♥ void

... - ... - ... - ... - 4♠ = ♣ void

... - ... - 4♣♦♥ = singleton maxi-splinter

3NT = normal splinter with any void

... - 4♣ asks

... - ... - 4♦ = ♦ void

... - ... - 4♥ = ♥ void

... - ... - 4♠ = ♣ void

4♣♦♥ = normal splinter with a singleton

 

In this way you keep your splinter ranges tight while avoiding ambiguity as well as polution of the generic GF raise. Against that, 5 responses have been used up, so auctions offering enough bidding space to use this type of structure tend to be extremely limited. It is easily possible on the initial response though and something I would recommend advanced partnerships to try out if they can afford the bidding space required.

[miamijd]

There is an excellent alternative to this - having 2 splinter ranges. If you are not worried about the singleton/void amibguity then you can use the structure I posted previously:-

 

1♠

==

3NT = maxi-splinter in any suit

... - 4♣ asks

... - ... - 4♦ = 0-1 diamonds

... - ... - 4♥ = 0-1 hearts

... - ... - 4♠ = 0-1 clubs

4♣♦♥ = normal splinter

==

 

A second alternative is to use an additional response to cover these hands, for example:-

 

1♠

==

3♥ = any maxi-splinter

... - 3♠ asks

... - ... - 3NT = any void

... - ... - ... - 4♣ asks

... - ... - ... - ... - 4♦ = ♦ void

... - ... - ... - ... - 4♥ = ♥ void

... - ... - ... - ... - 4♠ = ♣ void

... - ... - 4♣♦♥ = singleton maxi-splinter

3NT = normal splinter with any void

... - 4♣ asks

... - ... - 4♦ = ♦ void

... - ... - 4♥ = ♥ void

... - ... - 4♠ = ♣ void

4♣♦♥ = normal splinter with a singleton

 

In this way you keep your splinter ranges tight while avoiding ambiguity as well as polution of the generic GF raise. Against that, 5 responses have been used up, so auctions offering enough bidding space to use this type of structure tend to be extremely limited. It is easily possible on the initial response though and something I would recommend advanced partnerships to try out if they can afford the bidding space required.

 

So 3NT is supposed to be a "mid-range' hand: better than a minimum splinter but not a really good hand, which makes the GF 4+ trump raise? Or is 3NT supposed to be the really good hand, with the mid-range hands not making the splinter? Or is 3NT supposed to be any splinter better than a minimum?

 

I think the first treatment is OK, but it robs you of a lot of bidding room (you even lose "Last Train" when the stiff is in H or C, rather than just in H). Do you think you gain a lot over a simple 4+ GF raise (whatever you use for that)? I'm not sure you do (I think the 4+ GF raise might be superior here).

 

The second treatment doesn't work well. Why jump the bidding that much with a moose?

 

The third treatment I think is unworkable, because your partner can't tell your strength and there's no room left to find out.

 

I suppose you could use regular splinters for minimums; 3NT for the intermediates; and 3H for the maximums, but why? If you have a good hand, aren't you better off keeping the bidding low and finding out about partner's hand by making a simple 4+ GF raise? In addition, losing the 3H bid over 1S is a problem. You need this to show the 9-11 6+H hand.

 

Cheers,

Mike

[Trick13]

We have started putting 6 ranges of splinter into 1M - 1M+1 ...

 

After 1♥ - 2♠; 2NT ...

==========================

3♣ ... unspecified singleton or void, 10-12, relay asks

3♦ ... unspecified singleton or void, 13-15, relay asks

3♥ ... unspecified void, 16+, relay asks

3♠ ... Low singleton (♣), 16+

3N ... Middle singleton, 16+

4♣ ... High singleton, 16+

 

This frees up the double jumps combined with some other bids we have available (because we use transfer responses) for fit jumps. We can show 9 patterns in the fit jump suit ...

HHHxx / HHxxx / Hxxxx each with 0-1 / 2 / 3 cover cards in the other two suits

 

The thinking is that while splinters can identify wastage, the fit jumps can identify a source of tricks.

 

Other hands can bid Jacoby (2M+2) to enquire about opener's shape and range, or establish a game force at 2M after which we show controls (1st/2nd). The advantage of showing controls is to stay low when you find a suit neither of you control; you can otherwise use keycard to ensure you have enough first round controls.

[Zelandakh]

So 3NT is supposed to be a "mid-range' hand: better than a minimum splinter but not a really good hand, which makes the GF 4+ trump raise? Or is 3NT supposed to be the really good hand, with the mid-range hands not making the splinter? Or is 3NT supposed to be any splinter better than a minimum?

The splinter range you defined in your original post could be described as 12-15 including distribution (or 9-12 with a singleton if you prefer). The maxi-splinter represents a similar range of hands but shifted upwards, something like 16-19 (13-16 + sgl). With a hand stronger than this, the traditional way of bidding is to choose between making a normal splinter and continue on above 4M or go through the GF raise on the basis that you want to take control. This does not change when using maxi-splinters.

[Zelandakh]

We have started putting 6 ranges of splinter into 1M - 1M+1 ...

 

After 1♥ - 2♠; 2NT ...

==========================

3♣ ... unspecified singleton or void, 10-12, relay asks

The problem with this scheme is that you cannot show all mini-splinters below 3M, meaning that Opener can be in the position of not being able to ask for fear of getting too high but nonetheless wanting to play in game opposite some hands. There is a solution to that using a similar trick to two-way game tries but it makes things considerably more complicated.

 

I actually use a related scheme myself rather than the 3♥ maxi-splinter response but was keeping it simple by avoiding the subject of mini-splinters:-

 

1♠

==

2NT = any mini-splinter or any maxi-splinter

... - 3♣ asks

... - ... - 3♦ = mini-splinter with diamond shortage

... - ... - 3♥ = mini-splinter with heart shortage

... - ... - 3♠ = mini-splinter with club shortage

... - ... - 3NT = any void maxi-splinter

... - ... - ... - 4♣ asks

... - ... - ... - ... - 4♦ = ♦ void

... - ... - ... - ... - 4♥ = ♥ void

... - ... - ... - ... - 4♠ = ♣ void

... - ... - 4♣♦♥ = singleton maxi-splinter

3♣ = GF raise

3NT = normal splinter with any void

... - 4♣ asks

... - ... - 4♦ = ♦ void

... - ... - 4♥ = ♥ void

... - ... - 4♠ = ♣ void

4♣♦♥ = normal splinter with a singleton

==

 

Both schemes involve bumping the GF raise over 1♠ up to 3♣. Yours saves a step on the maxi-splinters and frees up the double jumps at the cost of losing 2 steps on the mini-splinter hands. Unfortuntely those 2 steps are fairly important and as mini-splinters are a lot more common I wonder if you are really getting enough back to compensate. Given your transfer responses it seems that you ought to have enough bidding space to transfer and jump on those fit jumps and therefore be able to keep the normal splinter responses without really losing anything.

[Trick13]

The problem with this scheme is that you cannot show all mini-splinters below 3M, meaning that Opener can be in the position of not being able to ask for fear of getting too high but nonetheless wanting to play in game opposite some hands.....

 

We used the same scheme for mini-spinters until recently.

 

 

Now we put mini-splinters in 1M - 2M (9-11 no shortage or 7-9 mini-splinter) and use 3-way game tries.

All the splinters in 1M - 2M+1 are now game force.

Hands with support that are just short of a good raise go through a range finder, and for weaker hands we have a pre-emptive raise to the 2-level.

Good 4-card invites, 10-11, go through 1M - 2M+3, which also includes the HHHxx fit raise; and 12-13 raises are included in Jacoby 1M - 2M+2.

All of this to accommodate the fit jump raises.

 

 

[msjennifer]

Over major-suit openings, I can show voids, so splinters are always singletons; but we can do this only directly.

 

As far as control bids go, it is typical to bid first and second round controls below game; above game control bids are usually first round.

I fully agree.Playing Super Precision opener can not make a splinter bid.In that system ,as well as others ,controls are shown as you said.

[Zelandakh]

I fully agree.Playing Super Precision opener can not make a splinter bid.

What does it use sequences such as 1♥ - 1♠; 4m for instead?

[Vampyr]

What does it use sequences such as 1♥ - 1♠; 4m for instead?

 

For me it is a splinter; sorry if my post was unclear.

[Zelandakh]

For me it is a splinter; sorry if my post was unclear.

I think for most people - but msjennifer wrote that Super Precision does not offer Opener this option, so I was wondering what the alternative there is. It is undocumented in the SP sources I have so I would have expected its normal meaning (splinter) to be retained.

[Stefan_O]

The reason I'm asking is that I like the unambiguous clarity of splinters and control bids showing *only* Aces and voids, and I hate the ambiguity introduced by also allowing singletons (usually as part of Splinters).

 

Simply put, short of a ruff or an over-ruff, an Ace or a void are cast-iron first round controls. A singleton isn't.

 

What do others think?

 

D.

 

Short story:

 

The general strategy in standard suit-slambidding is:

 

1. Establish that you have enough combined playing-strength to make a slam likely/playable.

 

2. Use control-bids to ensure opponents cannot cash two quick tricks in the same suit.

 

3. Use RKCB to ensure you do not have two possible top-losers.

 

Thus, following this scheme, you don't care too much whether a control is King, Ace or a singleton -- often you don't need to know.

 

The thing that requires special handling only is voids -- since you may then have a slam even with two keycards missing.

There are tools like void-splinters, and unusual RKCB answers that can sometimes handle these.

[pescetom]

Limiting splinters to voids only is a huge loss. Since singletons are much more common than voids, you lose the ability to splinter on about two thirds of potential hands.

 

Two thirds sounds like a conservative estimate to me. The probability that a hand contains a singleton is about 33.6% and that it contains a void about 4.9%. Those are generic probabilities - not specific to hands with a major fit - but you get the picture.

[Vampyr]

I think for most people - but msjennifer wrote that Super Precision does not offer Opener this option, so I was wondering what the alternative there is. It is undocumented in the SP sources I have so I would have expected its normal meaning (splinter) to be retained.

 

Perhaps it is Fruit Machine Swiss.