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Percentage Play Mixed Teams Pula

#1 User is offline   lamford 

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Posted 2019-September-16, 11:17


West leads the king of spades, and East encourages and they cash four rounds, West starting with KQJx. Now West exits with the J and East plays the 5 (reverse count if anything). East had discarded 3 suggesting a club, on the fourth spade. You win, perforce. Over to you.

[More details given after mikeh's justified protestations]
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#2 User is offline   kuhchung 

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Posted 2019-September-16, 12:51

i admit i only see one line...
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#3 User is offline   KingCovert 

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Posted 2019-September-16, 13:17

Well, you probably have to overtake the Q. I mean, how else do you take two diamond hooks? Hoping for a doubleton K is sadly smaller odds than a doubleton J, so we depressingly play A, Q overtaken by the K, pray for the jack to fall, take the diamond hook, and cross in hearts again. Cashing the hearts and claiming the good tricks in dummy.

This hand has a major entry problem. You can't afford to lose another trick, so... What else can you do? There isn't a third club trick coming. 4, 3, 2, or you're just never making.
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#4 User is offline   Cyberyeti 

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Posted 2019-September-16, 14:00

View Postkuhchung, on 2019-September-16, 12:51, said:

i admit i only see one line...


There is a second, but the carding indicates it won't work, W could be 4234 and squeezed if you cash the top clubs and 4 hearts.
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#5 User is offline   FelicityR 

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Posted 2019-September-16, 14:22

My line would to finesse the 10 and then play for a 3-3 split in s overtaking the Q on the third round. Finding West with JX or J is about 8-10% I feel whereas the immediate finesse after the K, is half of 36% (18%)

[I have probably got this wrong, if so I apologise.]
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#6 User is offline   lamford 

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Posted 2019-September-17, 07:55

View PostFelicityR, on 2019-September-16, 14:22, said:

My line would to finesse the 10 and then play for a 3-3 split in s overtaking the Q on the third round. Finding West with JX or J is about 8-10% I feel whereas the immediate finesse after the K, is half of 36% (18%)

[I have probably got this wrong, if so I apologise.]

Your line would be right if East is dead from the neck up and fails to insert the jack from Jxx when AQx is visible in dummy.

There are two remaining lines, ace, and then queen of hearts, one overtaking, the other not. If East plays the jack of hearts on the second round, you obviously overtake, and if the jack of hearts is stiff you know what to do. The rest of the time?
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#7 User is offline   mikeh 

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Posted 2019-September-17, 14:22

It may be that the missing information would have little, if any, effect on the choice of line, but this is yet another instance of a play problem being presented with hardly any of the information that we would have were we really declarer.

Hint: just because you, as the poster, don't think full information is relevant doesn't make it so.

For example, at the table I'd have some possibly useful, possibly non-informative information about the club suit. Which club did RHO return and which club did LHO play, and what are their signaling methods?

While I'm on my rant, wtf is a mckenny signal? Why not say 'encouraging' or 'discouraging' or 'suggests clubs' etc...in other words provide the information that declarer would have.

There's a current thread on BW where the OP had an opp tank for a long time before resolving a 2-way guess to land a slam, and his premise was that declarer had no reason to take so long, unless he was unethically attempting to read the defender's mannerisms. As most responses pointed out, a skilled player sees far more information in the cards than does a less skilled player. So: please, please don't assume that just because you don't think information matters that it doesn't. How much time does it take to specify who played what and what the opps' carding agreements are?

end rant

If I have an inference available about the clubs, that may affect my assumptions about the red suits. If I think RHO is short in clubs, and I know he has 3 spades and I infer some diamond length (which might depend on knowing what diamond he pitched and what a mckenny signal means) then if he has short clubs, he will have heart length. Then, low towards the K109x, intending to play the 10, might be attractive if I think East is the sort of player who would robotically play low from Jxx(x). But if I think him to be sharper than that, an inference about heart length might cause me to play for west to have Jx, and so on.

I suspect that at the table I'd be in the tank for a long time, but here I won't bother, because I lack the information that I consider relevant.
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#8 User is offline   nige1 

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Posted 2019-September-17, 16:00

lamford 'West leads the king of spades, and East encourages and they cash four rounds, West starting with KQJx. Now West exits with a club. East had discarded a small diamond, McKenny, on the fourth spade. You win, perforce. Over to you.
++++++++++++++++++++++++++
As I grow older I find it harder to pay attention to defenders' carding.
But perhaps declarer should take Paul's (implied) advice
Win the switch with K. and cash AQ.
-- If RHO follows with J then overtake with K to take 2 finesses.
-- Otherwise, cash A and finesse T,
playing for CyberYeti's minor-suit squeeze.
winning when LHO has K and 4+s (or the hand on the left).

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#9 User is offline   ahydra 

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Posted 2019-September-17, 19:32

View Postmikeh, on 2019-September-17, 14:22, said:

While I'm on my rant, wtf is a mckenny signal? Why not say 'encouraging' or 'discouraging' or 'suggests clubs' etc...in other words provide the information that declarer would have.


I always thought it was spelt McKenney, but anyway, it's otherwise known as Lavinthal or simply "suit preference". High card = suggests values in the higher of the other two suits, low card = in the lower of the other two suits. So here East's small diamond suggests he has a club card. At a club level I'd be happy to take this at face value and play for the overtake. At a top level, of course East might try to mislead declarer into not playing for the squeeze when it's there all along.

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#10 User is offline   nige1 

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Posted 2019-September-18, 01:39

Suppose declarer wins LHO's shift with K,
cashes AQ (both following). Then cashes A.
Surprisingly, however, LHO shows out.
Now, if LHO has K, declarer can't pick it up,
So he might as well cash A, rewarded when
-- RHO was dealt singleton K or
-- RHO discarded a from doubleton K.
In these cases, it might have been a better defence
for LHO to switch to a .

On reflection, perhaps, a superior line is for declarer
to cash both s before playing Q.
If LHO shows out on the top s, then
declarer's best hope might be to overtake Q
hoping LHO has K and Jx doubleton.

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#11 User is offline   lamford 

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Posted 2019-September-18, 13:52

The winning line was to overtake the Q, as West had Jx and the king of diamonds. This is around 8%. I thought a slightly better line was to cash the queen of hearts, overtaking only if East has Jx (when both lines work). If hearts produce 4 tricks you need West to have Kx or QJT of clubs and the king of diamonds. I pick up hearts 5-1 with the diamonds coming in or the squeeze. A rough calculation made this a bit over 8.5% but there is little in it.
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#12 User is offline   Cyberyeti 

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Posted 2019-September-18, 14:17

View Postlamford, on 2019-September-18, 13:52, said:

The winning line was to overtake the Q, as West had Jx and the king of diamonds. This is around 8%. I thought a slightly better line was to cash the queen of hearts, overtaking only if East has Jx (when both lines work). If hearts produce 4 tricks you need West to have Kx or QJT of clubs and the king of diamonds. I pick up hearts 5-1 with the diamonds coming in or the squeeze. A rough calculation made this a bit over 8.5% but there is little in it.


You don't need QJ10, any 4 will do, but the McKenny signal would indicate the clubs are not like that so overtaking is also unlikely to work but more likely than the squeeze
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#13 User is offline   KingCovert 

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Posted 2019-September-18, 14:32

View Postlamford, on 2019-September-18, 13:52, said:

The winning line was to overtake the Q, as West had Jx and the king of diamonds. This is around 8%. I thought a slightly better line was to cash the queen of hearts, overtaking only if East has Jx (when both lines work). If hearts produce 4 tricks you need West to have Kx or QJT of clubs and the king of diamonds. I pick up hearts 5-1 with the diamonds coming in or the squeeze. A rough calculation made this a bit over 8.5% but there is little in it.


There are pretty much only two lines worth considering:

A, Q, Finesse the J. Which only wins if the K is doubleton in West or singleton.
(1/2 of 3-3 breaks) or (2/3 of 4-2 breaks) in AND (2/7 of 1/2 of 5-2 breaks) or (all 6-1 breaks) in . Notice the AND.

A, Q overtaken by the K. Which only wins if the J is doubleton in either hand and the finesse works.
(1/3 of 4-2 breaks) in AND (6/7 of 1/2 of 6-1 breaks) or (1/2 of 5-2 breaks) or (1/2 of 4-3 breaks) in .

Notice that if you play A and 3 intending to put in the T, You can't do this planning to overtake the Q later. If opponent rises with the J in the second round of hearts the suit blocks. Down 1.

If you want to crunch the numbers you can, but it's really the only line of play. Anything else is honestly kind of silly.
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#14 User is offline   Cyberyeti 

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Posted 2019-September-18, 15:13

View PostKingCovert, on 2019-September-18, 14:32, said:

There are pretty much only two lines worth considering:

A, Q, Finesse the J. Which only wins if the K is doubleton in West or singleton.
(1/2 of 3-3 breaks) or (2/3 of 4-2 breaks) in AND (2/7 of 1/2 of 5-2 breaks) or (all 6-1 breaks) in . Notice the AND.

A, Q overtaken by the K. Which only wins if the J is doubleton in either hand and the finesse works.
(1/3 of 4-2 breaks) in AND (6/7 of 1/2 of 6-1 breaks) or (1/2 of 5-2 breaks) or (1/2 of 4-3 breaks) in .

Notice that if you play A and 3 intending to put in the T, You can't do this planning to overtake the Q later. If opponent rises with the J in the second round of hearts the suit blocks. Down 1.

If you want to crunch the numbers you can, but it's really the only line of play. Anything else is honestly kind of silly.


In practice with the signal for clubs this may be true, but in theory W K to 3 or more AND sole control of clubs (QJ10 or any 4) is sufficient if you can take 4 heart tricks.
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#15 User is offline   lamford 

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Posted 2019-September-18, 16:03

View PostCyberyeti, on 2019-September-18, 15:13, said:

In practice with the signal for clubs this may be true, but in theory W K to 3 or more AND sole control of clubs (QJ10 or any 4) is sufficient if you can take 4 heart tricks.

Indeed, at the table, I was lured by the layout of East having Jxxxx when I only need him to have four diamonds with no king. West is never going to play anything other than a club, whatever the signal. I think my line is quite a bit better now on more calculation, getting on for 10%.

I also mused about the second round heart finesse, and reflected that if RR was East he would insert the J from Jxx because he had a heart in with his diamonds. His guardian angel would, of course, allow him to find it in time to avoid a revoke.
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