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Splinters and control bids What do you play?

#21 User is offline   Vampyr 

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Posted 2017-October-20, 03:17

View PostZelandakh, on 2017-October-20, 03:13, said:

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


For me it is a splinter; sorry if my post was unclear.
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#22 User is offline   Zelandakh 

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Posted 2017-October-20, 04:49

View PostVampyr, on 2017-October-20, 03:17, said:

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.
(-: Zel :-)
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#23 User is offline   Stefan_O 

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Posted 2017-October-20, 13:03

View PostDinarius, on 2017-October-18, 06:45, said:

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.
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#24 User is offline   pescetom 

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Posted 2017-October-21, 07:23

View PostJoe_Old, on 2017-October-19, 07:34, said:

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.
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#25 User is offline   Vampyr 

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Posted 2017-October-21, 19:14

View PostZelandakh, on 2017-October-20, 04:49, said:

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.
I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones -- Albert Einstein
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#26 User is offline   WesleyC 

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Posted 2017-November-05, 09:06

As others have already pointed out, splinters are a critical tool in modern slam bidding methods that allow you diagnose wasted values opposite the shortage. They should (generally) be shown separately to high card style controls for this reason.

However, no-one has yet mentioned that the main reason that most modern players prefer 1st/2nd round cuebids, is that the main purpose of the cuebid is to establish extra values and slam try without propelling the partnership to the 5-level.

To make an example: if an uncontested auction starts:

1S - 2H
3C - 3S

you might hold anything from:

[AKJxx x Qx KJTxx]

[AKJxx Qx x KJTxx]

[AKQJx Qx x KJTxx]

Although none of the above hands have a biddable first round control, their playing strength is vastly different.
Using 1st/2nd round controls and a last train slam try, you would easily be able to quantify those differences below the level of game.
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#27 User is offline   gszes 

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Posted 2017-November-20, 16:33

huge topic (might take a book) but long story short -- a singleton is NOWHERE AS USEFUL AS A VOID but it is still highly useful for a couple of reasons. If one fails to splinter and later shows a "control" in that suit it should be the ace or/and king (if partnership allows for kings. A splinter gives the partnership a tremendous strategic advantage since it allows for an immediate evaluation of how well the hands fit together for slam purposes. lets say responder has AQxxxx AK void xxxxx and p opens 1s. Responder bids 2n (jacoby 2n) and opener bids 3c (short). Responder has all the information they need to search for slam. They can ask opener later if they have a void and bid a grand. The bidding may never get off the ground if opener cannot show their short suit because they have a singleton. The bidding may also short circuit if responder (mistakenly) bids 4c splinter just because they have a void.
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#28 User is offline   nige1 

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Posted 2017-November-20, 19:10

Over Ms, there are lots of (mini)splinter schemes. Our effort quoted below.

Over ms, especially if they normally show 4 cards, Eric Crowhurst recommended what he called minor-suit Swiss nowadays known as fit-jumps, showing 5+ of the bid suit and 4+support. They seem to work well.

View Postnige1, on 2017-September-16, 17:25, said:

After 1M we've recently agreed a simple mini-splinter structure. e.g. after 1 - ??
  • 1 = NAT
  • 1N = NAT NF 6-11
  • 2 = REL 12+. F1. Artificial. Then 2 = ART Sound opener.
  • 2 = TRF 8+ 3 s. Good raise to at least 2.
  • 2 = NAT 0-8. Poor raise.
  • 2 = SPL any singleton). 4+ raise to 3 or 5. Then 2N = ASK for singleton?
  • 2N = ART. BAL or void. 4+ raise to 3 or 5. Then 3 = ASK whiich?
  • 3/ = SPL this void. 4+ raise to 3 or 5.
  • 3 = PRE
  • 3 - 4 = Same but game raise.

Similarly after 1 - ??
  • 1N = NAT NF 6-11.
  • 2 = REL.
  • 2 = TRF 5+ s.
  • 2 = TRF Good 3+ raise.
  • 2 = NAT 0-8.
  • 2N = SPL 4+ any singleton. 4+ raise to 3 or 5.
  • 3 = BAL or SPL void. 4+ raise to 3 or 5.
  • 3/3 = SPL this void. 4+ raise to 3 or 5.
  • 3 = PRE
  • 3N - 4 = Same but game raise.




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#29 User is offline   Zelandakh 

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Posted 2017-November-21, 00:41

You ought to be able to include your void maxi-splinters within the 2M+1 raise Nigel. That would open up the question whether using the 3M-1 and 3M-2 responses for some other purpose, such as moving your balanced game raise down a level, was worth more than the ability to show void mini-splinters.

1
==
1 = NAT
1N = NAT NF 6-11
2 = REL 12+. F1. Artificial. Then 2 = ART Sound opener.
2 = TRF 8+ 3 s. Good raise to at least 2.
2 = NAT 0-8. Poor raise.
2 = SPL any shortage. 4+ raise to 3 or 5. Then 2N = ASK (3m = raise to 3 with shortage; 3 = raise to 5 with any void; 3N4m = raise to 5 with singleton)
2N = ART. BAL. 4+ game raise.
3 = ART. BAL. 4+ raise to 3 or 5. Then 3 = ASK which?
3 = freed for another purpose (eg mixed raise)
3 = PRE
3 = 4+ game raise with any void
3N4m = 4+ game raise with singleton
4 = PRE
--

If you really want those void mini-splinters you could get them with a little light rearrangement and still save a little space for the balanced GF raise:

1
==
1 = NAT
1N = NAT NF 6-11
2 = REL 12+. F1. Artificial. Then 2 = ART Sound opener.
2 = TRF 8+ 3 s. Good raise to at least 2.
2 = NAT 0-8. Poor raise.
2 = either a) SPL any singleton. 4+ raise to 3; or b) SPL any shortage. 4+ raise to 5. Then 2N = ASK (3m = raise to 3 with singleton; 3 = raise to 5 with any void; 3N4m = raise to 5 with singleton)
2N = ART; either a) SPL or void. 4+ raise to 3; or b) BAL. 4+ game raise. Then 3 = ASK which.
3 = ART. BAL. 4+ raise to 3 or 5. Then 3 = ASK which?
3 = SPL, void. 4+ raise to 3.
3 = PRE
3 = 4+ game raise with any void
3N4m = 4+ game raise with singleton
4 = PRE
--

I think using 3NT/4 as your balanced game raise is pretty bad to be honest. This is a common and important hand type. Even the second scheme, which begins describing this hand at 3M+1, is tight for space. Using 3M+2, as in the first structure, is probably alone worth more than the void mini-splinters. Starting even higher just seems like a total no-go to me, similar to some of the older Swiss schemes that died out in the 80s.
(-: Zel :-)
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#30 User is offline   nige1 

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Posted 2017-November-21, 16:23

Thank you for your constructive comments on our schema, Zelandakh.

For completeness, I should mention that, after an ASK, we "run-on" with maxima.

For example, 1 - 2N - 3 - ??
  • 3 = SPL singleton. 4-card raise to 3 or 5.
  • 3 = SPL singleton. 4-card raise to 3 or 5.
  • 3 = SPL singleton. 4-card raise to 3.
  • 3N... = SPL singleton. 4-card raise to 5.

and, when continuing the auction, 3N is a serious slam-try.

In spite of its faults, the system has 3 merits.
  • Void splinters, singleton splinters, pudding and pre-emptive raises can be distinguished, at or below a 3-level raise.
  • Opener need reveal responder's singleton, only when he wants to know.
  • Considering its comprehensiveness, it's as simple and consistent as possible.

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