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A Tricky Trilemma

#1 User is online   lamford 

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Posted 2018-June-07, 16:09


This was the talk of the town today in the second day of the European Championship in Ostend. Your reporter sat out this match, so watched about half the field or so make this tough slam. West invariably led a small diamond (various methods) and you have a choice of lines.
a) To cash three clubs and then play a heart to the queen. If the clubs have behaved you claim; if not you take the heart finesse, assuming they have not cashed the long club!
b) Play a heart to the queen and then finesse the heart on the return when they attack your options, as all top defenders from Albania to Zimbabwe will do
c) Play a heart to the queen, rise on the heart return, and hope that the jack of hearts drops, clubs behave, or if not, spades do and you have a rounded suit squeeze.

The BSM, (British Scrabble Magazine, not British School of Motoring) once analysed a game by Mark Nyman, World Scrabble Champion, and said that he had a dilemma whether to play a low scoring word with a Z, whether to use the other letters for his best score, or whether to block his opponent. I pointed out that this was a trilemma. Such is the case here.
I prefer to give the lawmakers credit for stating things for a reason. - barmar
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#2 User is offline   ahydra 

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Posted 2018-June-07, 23:05

The first line is 36% + (64% of 25%), as you need the HA to be on the other side to the fourth club (just over 50%) and the HJ onside (50%). That adds up to 52%.

Staking everything on the heart finesse in the second line is 50%. There's a small extra chance that West will hop immediately when you lead a heart to the Q, of course, which then gives you bucketloads of chances for the 12th trick.

The third one is (very roughly) 20% to drop the HJ. (You pick up a 0-6 break as well, as the finesse is marked) For the squeeze you need the HJ with the long club which is (very roughly) 50%. So overall you have 20% + 80% * (36% + (64% * 36% * 50%)) = somewhere just short of 60%, which would appear to make it the favourite especially when combined with the extra chance of West hopping HA. I think this is the line I would play, not least because bringing 6NT home on a squeeze gains you a lot of style points :) Of course, if the defence decline to take HA on the first round, I suppose I have to fall back to line (b).

The voice commentators (Mark Horton and Peter Lund) were debating whether, when a player takes the HA and returns a heart immediately, you should divine that they are trying to convince you the jack is offside when in fact they have it. I guess, many expert defenders would do this regardless of whether they had the J or not.

ahydra
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#3 User is offline   cherdano 

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Posted 2018-June-08, 00:55

Well, I guess I am ducking with Axxx against ahydra!
Obviously we have a recall bias in favour of the assholes. -helene_t
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#4 User is online   lamford 

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Posted 2018-June-08, 01:43

And you are not home if the heart finesse wins. You are a huge favourite of course but I don't think you can quite claim on the double squeeze except against a Belgian side.
I prefer to give the lawmakers credit for stating things for a reason. - barmar
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#5 User is offline   dokoko 

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Posted 2018-July-03, 23:14

This in fact a dilemma.

Your problem is that you cannot test both hearts and clubs without giving up some options.

- If you start on hearts, defenders may force you to take a decision in the suit without knowing the club position.
- If you test clubs first, you may go down even if hearts behave.

A dilemma/trilemma is not just a situation where you have a certain number of options; it is necessary that every option involves a possible damage.

Solving a dilemma means to find a way to "have your cake and eat it", not just to guess right or find the percentage play. An example (not applicable here) would be a so-called "Discovery Play" where you play to get more info before deciding how to attack the critical suit.
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#6 User is offline   jallerton 

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Posted 2018-July-07, 15:49

View Postlamford, on 2018-June-07, 16:09, said:


This was the talk of the town today in the second day of the European Championship in Ostend. Your reporter sat out this match, so watched about half the field or so make this tough slam. West invariably led a small diamond (various methods) and you have a choice of lines.
a) To cash three clubs and then play a heart to the queen. If the clubs have behaved you claim; if not you take the heart finesse, assuming they have not cashed the long club!
b) Play a heart to the queen and then finesse the heart on the return when they attack your options, as all top defenders from Albania to Zimbabwe will do
c) Play a heart to the queen, rise on the heart return, and hope that the jack of hearts drops, clubs behave, or if not, spades do and you have a rounded suit squeeze.

The BSM, (British Scrabble Magazine, not British School of Motoring) once analysed a game by Mark Nyman, World Scrabble Champion, and said that he had a dilemma whether to play a low scoring word with a Z, whether to use the other letters for his best score, or whether to block his opponent. I pointed out that this was a trilemma. Such is the case here.


If you decide to go with [b] or [c], you may have a new trilemma if a heart to the queen holds.
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#7 User is offline   heart76 

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Posted 2018-July-24, 01:41

If you lead a to the Q and it holds, should you assume that the A is with W or are there layouts where E would duck?
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#8 User is online   nullve 

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Posted 2018-July-24, 03:20

View Postlamford, on 2018-June-07, 16:09, said:

West invariably led a small diamond (various methods) and you have a choice of lines.
a) To cash three clubs and then play a heart to the queen. If the clubs have behaved you claim; if not you take the heart finesse, assuming they have not cashed the long club!
b) Play a heart to the queen and then finesse the heart on the return when they attack your options, as all top defenders from Albania to Zimbabwe will do
c) Play a heart to the queen, rise on the heart return, and hope that the jack of hearts drops, clubs behave, or if not, spades do and you have a rounded suit squeeze.

d) Run the 8 at trick 2. If it loses to the J, it may not be obvious for LHO to continue hearts.
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#9 User is online   lamford 

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Posted 2018-July-27, 08:15

View Postjallerton, on 2018-July-07, 15:49, said:

If you decide to go with [b] or [c], you may have a new trilemma if a heart to the queen holds.

I suppose that the various combinations make this a hexlemma. Or does Emma have sex first?
I prefer to give the lawmakers credit for stating things for a reason. - barmar
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#10 User is online   lamford 

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Posted 2018-July-27, 08:20

View Postnullve, on 2018-July-24, 03:20, said:

d) Run the 8 at trick 2. If it loses to the J, it may not be obvious for LHO to continue hearts.

He will work it out if he is looking at the ace, and if he is not, then you still need clubs and spades to come in or the clubs behaving and a major suit squeeze.
I prefer to give the lawmakers credit for stating things for a reason. - barmar
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#11 User is offline   Fluffy 

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Posted 2018-August-07, 08:47

Lorenzini at my table started with AK, and noticed I played low-10, and my partner up-the-line (UDCA). I had some urge to play 10-low instead but setting up a possible finesse against my partner's Jxxx scared me enough not to do it.

Lorenzini did not cash third club and played Q instead, and then guessed to finesse on the heart back. We lost 17 IMPs. Would he have missguessed if I played 10-low?, I don't know.
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#12 User is online   lamford 

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Posted 2018-August-11, 06:33

View PostFluffy, on 2018-August-07, 08:47, said:

Lorenzini at my table started with AK, and noticed I played low-10, and my partner up-the-line (UDCA). I had some urge to play 10-low instead but setting up a possible finesse against my partner's Jxxx scared me enough not to do it.

Lorenzini did not cash third club and played Q instead, and then guessed to finesse on the heart back. We lost 17 IMPs. Would he have missguessed if I played 10-low?, I don't know.

Plackett, for Wales, did the same as Lorenzini, playing a heart to the queen, but then rose on the heart return, tested the clubs, and there was no squeeze. He matched your -17.
I prefer to give the lawmakers credit for stating things for a reason. - barmar
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