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Defensive signals Is there a "right" answer to this?

#1 User is offline   NickRW 

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Posted 2010-November-01, 12:31

This is a problem from the 1970 book, "Case for the Defence", by Victor Mollo (it may have been sold in the US under a different title). Mollo himself gave two answers, one of which he declares to be correct. To my mind there is a third possible answer - which seems to me to be at least as right.

I'll post the problem now - Mollo's answer in about 6 hours or so - after tonight's game...

West leads the spade queen.<br>East wins with the ace and returns the deuce on which declarer playes the King.<br>Which card should West play?

"Pass is your friend" - my brother in law - who likes to bid a lot.
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#2 User is offline   gnasher 

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Posted 2010-November-01, 12:44

The four, showing suit-preference for diamonds. I can't think of another answer, let alone two other answers.
... that would still not be conclusive proof, before someone wants to explain that to me as well as if I was a 5 year-old. - gwnn
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#3 User is offline   NickRW 

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Posted 2010-November-01, 12:56

View Postgnasher, on 2010-November-01, 12:44, said:

The four, showing suit-preference for diamonds. I can't think of another answer, let alone two other answers.


Ha, well you've got the answer I gave - the third option
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#4 User is offline   wank 

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Posted 2010-November-01, 14:55

i think the 10 would be just as obviously suit pref for diamonds.
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#5 User is offline   wyman 

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Posted 2010-November-01, 15:17

View Postwank, on 2010-November-01, 14:55, said:

i think the 10 would be just as obviously suit pref for diamonds.


In fact, the 7 should be just as obviously SP for diamonds; the only card partner has seen is the 3 or the 5, depending which declarer played. If partner believes that I hold 6 spades, my spade is not low.

Also, this is a little subtle; maybe it's obvious to everyone else that I can never want a club switch, but if delcarer now puts the HK on the table, I'm a little worried he might have a spade, 6 diamonds, and 2 hearts. I need to know how to hit partner, and if he plays the 4 -- I'm thinking club. Maybe I will still return a diamond, but I'd sure love to have had this conversation with partner before.

In theory, I should be able to signal hi-med-lo, and I'd love a "no preference" card, assuming partner can work out my approximate holding (which, given the spots, he should be able to).

When I first saw this hand, my first thought was S10, though I'm positive my regular partner would return a diamond if I played the S7.
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#6 User is offline   gnasher 

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Posted 2010-November-01, 15:32

View Postwyman, on 2010-November-01, 15:17, said:

Also, this is a little subtle; maybe it's obvious to everyone else that I can never want a club switch, but if delcarer now puts the HK on the table, I'm a little worried he might have a spade, 6 diamonds, and 2 hearts. I need to know how to hit partner, and if he plays the 4 -- I'm thinking club. Maybe I will still return a diamond, but I'd sure love to have had this conversation with partner before.


You're worried that declarer will lead K to partner's ace, and partner will now underlead his K? OK, so declarer makes two club tricks becfore he has to let me in to cash all my winners.
... that would still not be conclusive proof, before someone wants to explain that to me as well as if I was a 5 year-old. - gwnn
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#7 User is offline   Fluffy 

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Posted 2010-November-01, 15:40

I am worried that declarer bangs down A and catches partner's singleton K, when we might induce him not to do so by playing highest because he is stupid and then he will play us for KQ and nothing in the minors.

Partner is also suposed to duck A with nothing in diamonds when we clearly signaled for hearts and he is looking at the king himself, so we can then make a contradictional signal with Q that he will understand.
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#8 User is offline   Phil 

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Posted 2010-November-01, 15:45

I can imagine he might suggest the J as the card we are known to hold. Perhaps we are supposed to convince declarer spades are 4-4.

To what end eeither of these plays accomplishes I have no idea.

OTOH, when partner wins his singleton A, I think I know what suit I want him to return.
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#9 User is offline   wank 

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Posted 2010-November-01, 16:01

View PostPhil, on 2010-November-01, 15:45, said:

I can imagine he might suggest the J as the card we are known to hold. Perhaps we are supposed to convince declarer spades are 4-4.



we opened 2. i suspect declarer knows spades aren't breaking
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#10 User is offline   wank 

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Posted 2010-November-01, 16:03

View PostFluffy, on 2010-November-01, 15:40, said:

I am worried that declarer bangs down A and catches partner's singleton K, when we might induce him not to do so by playing highest because he is stupid and then he will play us for KQ and nothing in the minors.

Partner is also suposed to duck A with nothing in diamonds when we clearly signaled for hearts and he is looking at the king himself, so we can then make a contradictional signal with Q that he will understand.


that would give us a club void. it seems a little far-fetched to expect declarer to try to cross to dummy on diamonds, knowing he'll lose a trick to the ace (east's ace he hopes), in order to hook a club missing only Kx.
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#11 User is offline   NickRW 

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Posted 2010-November-01, 17:22

Well, Mollo said the right answer is the 10. He explains:

"Did you fail to get this right? Then you are in good company. One of America's leading pairs had their wires crossed in this situation during a friendly international. West played the 7, a middle card designed to show his entry was in the middle suit, diamonds."

"East argued, correctly, that since West was marked on the lead with the J10, the jack would signal hearts and the 10 would singnal for a diamond. The deuce (misprint - must mean the 4) would be the signal for clubs."

"West, a world champion, had overlooked the fact that he might have had no ace at all. That was what the 7, an essentially neutral card, suggested to East. When he came in the A, he returned a heart and..."

East's hand was
A2
87654
Q8732
A

Declarer held
K53
AKJ
T965
K43

So the actual West played the 7 to indicate a diamond. East and Mollo vote for the 10 and I thought, the same as gnasher, that surely a club would never be a preference with that dummy - so the 4 should be right.

It seems from the answers so far you all don't see it the same way either!

Nick
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#12 User is offline   gnasher 

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Posted 2010-November-01, 18:17

What was East playing for? For a diamond switch to let the contract through, declarer would have to have Kxx AKQJx Axx xx, which would make his line of play rather odd.

I think Mollo's point about the meanings of signals with this suit is generally correct, but I don't think this deal demonstrates that.
... that would still not be conclusive proof, before someone wants to explain that to me as well as if I was a 5 year-old. - gwnn
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#13 User is offline   cherdano 

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Posted 2010-November-01, 21:59

View Postgnasher, on 2010-November-01, 18:17, said:

What was East playing for? For a diamond switch to let the contract through, declarer would have to have Kxx AKQJx Axx xx, which would make his line of play rather odd.

I think Mollo's point about the meanings of signals with this suit is generally correct, but I don't think this deal demonstrates that.

I am surprised you agree, in particular since it disagrees with your earlier post!

To me, 4 would signal diamonds, Jack would signal hearts, and anything in between would be muddled. Not perfect but so far I never needed to signal for dummy's 8-card suit against NT.
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#14 User is offline   phil_20686 

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Posted 2010-November-02, 04:41

you might also consider throughing the Q or T or 9 of hearts (depending a bit on agreement - but one of these must command a diamond switch). I dont think that can ever let the contract through, and will fetch a diamond switch for sure I think. It also gets us one more undertrick... :)
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#15 User is offline   rhm 

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Posted 2010-November-02, 06:30

View PostNickRW, on 2010-November-01, 17:22, said:

Well, Mollo said the right answer is the 10. He explains:

"Did you fail to get this right? Then you are in good company. One of America's leading pairs had their wires crossed in this situation during a friendly international. West played the 7, a middle card designed to show his entry was in the middle suit, diamonds."

"East argued, correctly, that since West was marked on the lead with the J10, the jack would signal hearts and the 10 would singnal for a diamond. The deuce (misprint - must mean the 4) would be the signal for clubs."

"West, a world champion, had overlooked the fact that he might have had no ace at all. That was what the 7, an essentially neutral card, suggested to East. When he came in the A, he returned a heart and..."

East's hand was
A2
87654
Q8732
A

Declarer held
K53
AKJ
T965
K43

So the actual West played the 7 to indicate a diamond. East and Mollo vote for the 10 and I thought, the same as gnasher, that surely a club would never be a preference with that dummy - so the 4 should be right.

It seems from the answers so far you all don't see it the same way either!

Nick


Sorry, but what a nonsense. This analysis does not stand up in my view and it is a good example that most people rely too much on signals instead of applying simple Bridge logic.

If you apply logic this is a trivial hand from East's perspective.
If declarer holds both red aces and and a honor at least doubleton he will establish and claim 11 tricks.
Accordingly East has to play West for an ace in the red suit or a honor.

If West has a honor and South plays on the defense does not matter with the possible exception that East may have a singleton ace and that West may not go in with the king when a is let out of hand at trick 3. The hand will go down sooner or later.
So East need to concentrate only on which ace West to play for.
Accordingly East should return a unless West played specifically the jack at trick 2.

If South does not play on it is fairly clear that West's entry will be in .
(South would not bid 3NT with long and a singleton honor or a doubleton AK)

Most players would improve their defensive capability significantly if they would stop signaling for at least 6 months.

Rainer Herrmann
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#16 User is offline   dake50 

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Posted 2010-November-02, 07:11

Agree Rainer,
Most signals merely redundate what your bridge logic already determined.

The real problems come when 'that signal' was needed between two nearly equal cases.
Did I get the signal I needed? Or did partner go automatic? Asleep? Didn't see my problem?
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#17 User is offline   NickRW 

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Posted 2010-November-02, 10:15

View Postrhm, on 2010-November-02, 06:30, said:

Sorry, but what a nonsense.


Ah, well, the book is, apart from this one problem that is, I think, questionable, very good with a mix of mostly intermediate and some harder questions that the majority here should get mostly right in book form, but if we're honest, would miss a fair proportion of them at the table. I was just miffed at getting this question "wrong" and wondered if it was just me - or whether there was room for argument.

I also take your point - playing "unwanted cards" signals is quite a bit better than people think.

Nick
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#18 User is offline   Phil 

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Posted 2010-November-02, 10:40

View Postwank, on 2010-November-01, 16:01, said:

we opened 2. i suspect declarer knows spades aren't breaking


heh, true.

Showing a club card makes NO sense.
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#19 User is offline   pooltuna 

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Posted 2010-November-02, 11:24

View PostNickRW, on 2010-November-01, 12:56, said:

Ha, well you've got the answer I gave - the third option


If the J= then surely the T=
perhaps deception is in order so play the 4 to show to get declarer to either misplay the or try for 8 other tricks in / (if this is possible)
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#20 User is offline   gnasher 

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Posted 2010-November-02, 16:55

View Postcherdano, on 2010-November-01, 21:59, said:

I am surprised you agree, in particular since it disagrees with your earlier post!


Even though this is an internet forum, I do occasionally allow myself to be persuaded by other people's opinions. :)

Quote

To me, 4 would signal diamonds, Jack would signal hearts, and anything in between would be muddled. Not perfect but so far I never needed to signal for dummy's 8-card suit against NT.


What I meant was that if we did need to signal between three suits, the meanings should be as Mollo suggested.

Similarly, suppose that we were known to have a six-card suit, and had led the 4 playing 4th best. Then the 2 and 3 should be for the lowest and middle suits respectively.
... that would still not be conclusive proof, before someone wants to explain that to me as well as if I was a 5 year-old. - gwnn
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