[phil_20686]

So I thought this was an interesting question. On the one hand it demonstrates why you should always play your trump pips randomly when it doesnt matter, on the other I have observed that weaker players often play their trump pips from the bottom up, and this occasionally gives you an extra piece of information in the trump suit.

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RHO is a reasonable player, LHO is considerably weaker. Partner had a misunderstanding about the meaning of dble, so you reach 3!s. The lead is AK and another club. You cannot afford to have rho ruff this and switch to a heart so you ruff with the k!s, and cash the Q!s. Rho plays the 3 and lho plays the 8.

Now, how should you play in the spade suit? Obviously you cannot pick up 1-4 spades, and 4-1 is incredibly unlikely on the bidding. If you can trust lho to always play low from 8x and 7x, then you should drop as 8 is from J8 or 87. and its PRC, obviously you dont know for sure, but is the inference that weak players tend to play their trump pips from the bottom enough to tempt you to play for the drop, rather than finesse?

PS: How often do people draw inferences about a suit from the principle that your opponents have played the suit up the line.

[jschafer]

I'm not sure I agree with the view that LHO if always plays his smallest pips, he would play small from 85 but the 8 or 7 from 87. If he randomises from 87 he would probably also randomise from 85 and vice versa. Assuming he plays them up the line, LHO most likely has a singleton 8 or J8. You could still make it with ♠s 1-4 if LHO discards a ♥ on the ♠s or if he has something like 1-2-4-6 but that seems unlikely. I would play for the drop here and expect it to be % if LHO is a weak player.

[gnasher]

You didn't tell us how clubs broke, but given LHO's bidding I think he's quite likely to hold a singleton spade.

I think you went wrong at trick four. Instead of cashing dummy's top spade, I'd play a spade to the 10 immediately, retaining dummy's top spade as an entry for a second spade finesse. If spades are 1=4, I can now draw all four trumps.

Note that LHO can't beat me by holding off in diamonds - if he hasn't kept all of his clubs, I can afford to cash ♣J before playing a diamond; if he has kept all his clubs and three diamonds, he's thrown away ♥K.

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PS: How often do people draw inferences about a suit from the principle that your opponents have played the suit up the line.

Not often enough. However, it's not a simple as that, because you also have to consider whether they're giving suit preference. For example, if you were expecting him to give suit-preference for hearts, ♠8 doesn't mean very much, but ♠2 might mean that he has no other small cards.

[phil_20686]

gnasher, on 2011-January-30, 09:21, said:

You didn't tell us how clubs broke, but given LHO's bidding I think he's quite likely to hold a singleton spade.

I think you went wrong at trick four. Instead of cashing dummy's top spade, I'd play a spade to the 10 immediately, retaining dummy's top spade as an entry for a second spade finesse. If spades are 1=4, I can now draw all four trumps.

Note that LHO can't beat me by holding off in diamonds - if he hasn't kept all of his clubs, I can afford to cash ♣J before playing a diamond; if he has kept all his clubs and three diamonds, he's thrown away ♥K.


Not often enough. However, it's not a simple as that, because you also have to consider whether they're giving suit preference. For example, if you were expecting him to give suit-preference for hearts, ♠8 doesn't mean very much, but ♠2 might mean that he has no other small cards.

Clubs are 6-1. I could have taken an immeadeate spade finesse, but i did not beleive west could have a stiff spade and 6 clubs and not have a dble rather than a 3c bid. I am totally confident that lho would have dbled if 1-3-3-6 or 1-4-2-6, and less certain but still somewhat convinced that lho would dble with 1-2-4-6.

Moreover, maybe I was wrong, but it thought that if the ace of diamonds is on your left you cannot pick up 1-4 spades anyway, since lho can win the diamond you play to hand and prevent you casing the last club by exiting a diamond to strand you in dummy, and if you cash the club then lho will have winnings clubs to cash.

[gnasher]

phil_20686, on 2011-January-30, 09:51, said:

Clubs are 6-1. I could have taken an immeadeate spade finesse, but i did not beleive west could have a stiff spade and 6 clubs and not have a dble rather than a 3c bid. I am totally confident that lho would have dbled if 1-3-3-6 or 1-4-2-6, and less certain but still somewhat convinced that lho would dble with 1-2-4-6.

Suppose that you're certain that LHO will play upwards in trumps and randomly from equals. Comparing:

(1) Cash a top spade; if LHO plays 8 or 7, play for the drop, otherwise finesse
(2) Take a first-round spade finesse.

Line (1) gains against J8, J7 and singleton jack. Line (2) gains against 87 and four singletons.

Hence (1) is better if there's less than a 25% chance that spades are 1=4. Against most people, I'd expect the chance of 1=4 to be higher than that, but you know your opponents and I don't.

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Moreover, maybe I was wrong, but it thought that if the ace of diamonds is on your left you cannot pick up 1-4 spades anyway, since lho can win the diamond you play to hand and prevent you casing the last club by exiting a diamond to strand you in dummy, and if you cash the club then lho will have winnings clubs to cash.

That's what I was talking about in the third paragraph of my earlier post. For this defence to work, LHO has to:
- Keep three clubs - otherwise I can just cash ♣J before playing diamonds
- Keep ♦Axxx - if he keeps only Axx and then holds up twice, the third diamond will endplay him.
- Keep ♥Kx - otherwise I have two heart tricks
- Play to the first seven tricks.

3+4+2+7 = 16.