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Commonwealth Challenge Interesting Slam

#1 User is offline   lamford 

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Posted 2014-September-09, 09:27


IMPs; Six Clubs by South. Opening Lead K. Plan the play. If you know the hand, still comment, but do not indicate the winning line.
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#2 User is offline   mikeh 

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Posted 2014-September-09, 09:43

well, seems to me that we win the diamond A and run 7 rounds of trump, reducing dummy to AQ of spades and some small hearts or spades, matters not.

We will be playing LHO for no more than 2 hearts, tho he can have longer provided he is missing all of the QJ10, and of course we play for RHO to hold the spade K.

There is a 5 card end position and he has to have either stiffed his spade K (best defence if the cards allow it) or have come down to Kx and 3 hearts. We cash the heart AK and exit, unless we suspect he has stiffed his spade.

All kinds of things can go wrong here, of course, but this seems better than the spade hook.
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#3 User is offline   gszes 

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Posted 2014-September-09, 10:25

Looks like MIKEH with the jackpot yet again how come we can't get this player
to represent the bbo forum posters vs JEC we might stand a chance:)
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#4 User is offline   ahydra 

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Posted 2014-September-09, 11:03

I like mikeh's squeeze-endplay line. Looks like best odds though knowing my luck LHO will have Qxx :(

ahydra
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#5 User is offline   lamford 

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Posted 2014-September-09, 11:21

West turns up with one club to East's three, and the main problem with the squeeze endplay is that you then need West to have only two hearts. It would be nice to duck the king of diamonds, but this does not guarantee success. Also East may well have a singleton diamond. I think we should just take the spade finesse, because we will have to read the ending when East bares the king of spades anyway, and there may well be no ending. A top player went off playing mikeh's line. If I had to guess, I would say the spade finesse was around 40%, and the squeeze line maybe as low as 25% against good defenders.

This post has been edited by lamford: 2014-September-10, 19:54

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#6 User is offline   PhantomSac 

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Posted 2014-September-09, 13:10

If we play for the squeeze line it seems like we must keep 2 diamonds in dummy to make it a lot better? That requires LHO to have come down to 2 diamonds as well (else we exit a diamond). E.g.

AQ
x
xx
--

x
AK9
T
---

Now, if LHO had the SK obviously they cannot be guarding hearts (else they pitched the SK). We now play AK of hearts. If LHO shows out they must come down to 1 spade, if RHO has 1 heart and 2 spades left we endplay them, if they have 2 hearts and 1 spade left spades are 1-1. If LHO follows twice we can play a heart and endplay RHO (hopefully). We are going down if LHO had 3 hearts and no SK but all lines go down in that case. This way we make when the SK is on and when the squeeze works as long as we get the diamond count right.
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#7 User is offline   PhilKing 

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Posted 2014-September-09, 15:20

There's quite a lot to be said for ducking the diamond.
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#8 User is offline   PhantomSac 

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Posted 2014-September-09, 15:24

View PostPhilKing, on 2014-September-09, 15:20, said:

Duck the lead imo.


psycho!
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#9 User is offline   PhilKing 

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Posted 2014-September-09, 15:28

View PostPhantomSac, on 2014-September-09, 15:24, said:

psycho!


I am forbidden from saying whether or not it makes the hand completely laydown.
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#10 User is offline   wanoff 

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Posted 2014-September-10, 02:41

View PostPhilKing, on 2014-September-09, 15:28, said:

....... whether or not it makes the hand completely laydown.


Not.

If you're going to make the assumption that diamonds are 6-2 then on a spade switch at trick 2, slam is <50%.
Whereas following Phantom's line was 100%, and so it proved except declarer pitched his threat card before the squeeze.
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#11 User is offline   lamford 

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Posted 2014-September-10, 03:16

View PostPhantomSac, on 2014-September-09, 13:10, said:

We are going down if LHO had 3 hearts and no SK but all lines go down in that case.

Let us just deal with that false statement before I comment more generally. If LHO has three hearts and no SK, you have two chances, one is that he is Jxx Jxx KQJxxx x when your only winning line is to duck the diamond. The other is that he is Jx Jxx KQJxxxx x when your only winning line is to win the diamond and play the ace and queen of spades. Similar lines exist where the clubs are 2-2. The problem with your analysis is that you will have no means (against good players) of establishing whether the hearts are 3-4 or 2-5, where the king and jack of spades are, whether the king of spades has been bared (on either side) and whether diamonds are 6-2 or 7-1. I have so far gone through 24 hands consistent with the auction, and, while your line, or other lines, worked more often than the simple spade finesse, they often required one to cheat by looking at the opponents' cards. In the 24 hands I dealt, which is admittedly a small sample, the spade finesse worked on nine of them (which accords with the expected value of 6.5/18), and your line worked on six. Ducking the first diamond only worked on five, but given that West has 6-7 diamonds (the condition I set) that is unsurprising. For what it is worth, I would have won the opening lead, drawn trumps, and taken the spade finesse, and I would have been 25 IMPs better off than the actual declarer. But then I know little about squeezes or endplays, so I can only use the tools I have.
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#12 User is offline   lamford 

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Posted 2014-September-10, 03:23

View Postwanoff, on 2014-September-10, 02:41, said:

and so it proved except declarer pitched his threat card before the squeeze.

I think that was an error by the Vugraph operator, as declarer then exited with the heart when East was known to have two left and West none according to the official record, when declarer could still have taken the spade finesse.
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#13 User is offline   wanoff 

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Posted 2014-September-10, 04:15

View Postlamford, on 2014-September-10, 03:23, said:

I think that was an error by the Vugraph operator, as declarer then exited with the heart when East was known to have two left and West none according to the official record, when declarer could still have taken the spade finesse.


Not likely. If the diamond threat had been kept, spades would have been known to be 1-1 after the last heart.
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#14 User is offline   lamford 

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Posted 2014-September-10, 04:34

View Postwanoff, on 2014-September-10, 04:15, said:

Not likely. If the diamond threat had been kept, spades would have been known to be 1-1 after the last heart.

No, there were two hearts still out in the three card ending, according to the Vugraph archive. Unless it has been corrected since I last looked at it.

This was the ending with the lead in South. My guess is that declarer played a spade to the ace and went off, especially as West had just discarded on the king of hearts. It was not too late to play a spade to the queen as West was known to have started life with 3-3-6-1 shape. Declarer's line on BBO was misère, as there was no legitimate line, other than the spade finesse, after declarer won the opening diamond lead and West turned up with three hearts.
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#15 User is offline   rhm 

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Posted 2014-September-10, 06:54

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#16 User is offline   rhm 

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Posted 2014-September-10, 06:58

View Postlamford, on 2014-September-10, 04:34, said:

No, there were two hearts still out in the three card ending, according to the Vugraph archive. Unless it has been corrected since I last looked at it.

This was the ending with the lead in South. My guess is that declarer played a spade to the ace and went off, especially as West had just discarded on the king of hearts. It was not too late to play a spade to the queen as West was known to have started life with 3-3-6-1 shape. Declarer's line on BBO was misère, as there was no legitimate line, other than the spade finesse, after declarer won the opening diamond lead and West turned up with three hearts.

Maybe I am missing something
The 4 card ending would have been more enlightening.
If dummy keeps 2 diamonds and 2 spades (essentially phantomsac's position, which I think is right and should win far more often), how is West escaping the spade diamond squeeze on the heart king?
Due to the T West can not unblock even if diamonds are 6-2. This assumes that West has the J if he has only 6 diamonds for his 3 level overcall.
I can see that declarer might go wrong in the 4 card ending if East has the 7 or 9 and has kept it:

When South plays the heart king and West discards the J declarer could go wrong, but then East would have had to discard all his spades early, a very difficult defense.
Of course declarer could also go wrong if East had kept a spade instead of a heart, but he must keep the 7 or 9, which is anything but obvious (and was not the case above).
To start with in 30% of all cases where diamonds are 6-2 East will have only smaller diamonds

Rainer Herrmann
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#17 User is offline   lamford 

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Posted 2014-September-10, 10:49

View Postrhm, on 2014-September-10, 06:58, said:

Maybe I am missing something
The 4 card ending would have been more enlightening.
If dummy keeps 2 diamonds and 2 spades (essentially phantomsac's position, which I think is right and should win far more often), how is West escaping the spade diamond squeeze on the heart king?
Rainer Herrmann

I think you are right that you will usually make the contract in your ending. However, when West has the king of spades, the simple finesse works. We are really only concerned with lines where the king of spades is wrong, and, if you try to throw East in, you will fail sometimes when he has bared the king of spades and sometimes when he did not have it.
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#18 User is offline   PhilKing 

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Posted 2014-September-10, 15:06

View Postwanoff, on 2014-September-10, 02:41, said:

Not.

If you're going to make the assumption that diamonds are 6-2 then on a spade switch at trick 2, slam is <50%.
Whereas following Phantom's line was 100%, and so it proved except declarer pitched his threat card before the squeeze.


Why is a spade switch relevant?

Unless I am being a bit thick, I can just rise and run trumps.
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#19 User is offline   helene_t 

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Posted 2014-September-10, 16:49

View PostPhilKing, on 2014-September-10, 15:06, said:

Why is a spade switch relevant?

Unless I am being a bit thick, I can just rise and run trumps.

But then the queen of spades is not a menace anymore as you have no entries to it
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#20 User is offline   lamford 

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Posted 2014-September-10, 18:21

View PostPhilKing, on 2014-September-10, 15:06, said:

Why is a spade switch relevant?

Unless I am being a bit thick, I can just rise and run trumps.

I agree, and I think Helene is wrong. The only downside of ducking the diamond is that they may ruff the second round. However, it is by no means cold if you survive the first hurdle, and I still maintain the correct line is to win the first diamond, draw trumps and take the spade finesse. If you duck the diamond, the defenders play a second diamond and may reach this ending, with the lead in South:

Now the only winning line is to cash the ace of spades, but that will be wrong on other layouts.

And if West is xxx Jxx KQJxxx x, then he has already "fluffed his lines" by not finding the initial small heart lead, leaving declarer with no resource :)
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