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defend a slam with THREE aces N/B problem

#1 User is offline   manudude03 

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Posted 2020-December-13, 13:19



You are North on this hand and probably thinking the opps have gone mad when they bid 6. Partner, taking your double as lightner (asking for an unusual lead), leads the 4 which is won in dummy (declarer playing the 7). The 7 is then led from dummy, you duck (agree?), declarer wins the jack while partner plays the ten. Declarer then leads the 3 to which partner discards the 5 (encouraging). How do you defend?

Adv+ please hide answers in [ spoiler ] tags.
Wayne Somerville
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#2 User is offline   Cyberyeti 

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Posted 2020-December-13, 15:45

This is a good N/B problem which I won't spoil
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#3 User is offline   Zelandakh 

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Posted 2020-December-13, 20:48

Spoiler

(-: Zel :-)

Happy New Year everyone!
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#4 User is offline   LBengtsson 

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Posted 2020-December-14, 06:26

Good bridge problem. Zelandakh spoiler covers the bases. Think tricks declarer can take once A has gone. Think about dummy entries. Think about how dummy can get an extra trick also - how? Now do you see solution. You only want one ace other than A to make for slam to be down, not two.

Technique to solution is same as when you are defense and declarer can make by ruffing. What do you do then? easy when you see logic of problem.
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#5 User is offline   manudude03 

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Posted 2021-January-15, 16:33

Full hand in spoilers, names changed to protect the guilty.

Spoiler

Wayne Somerville
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#6 User is offline   AL78 

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Posted 2021-January-25, 09:09

Seing both EW hands, why wouldn't declarer take a heart ruff before trying to draw trumps. They are down if the defender with the spade ace also held three diamonds and no more than two spades and leads a diamond for a ruff, but declarer is down whatever they do on that layout. It looks like declarer was playing for a defender with itchy fingers to try cashing an ace when in with the spade ace. That is the only chance I can see of a 12th tricks apart from a heart ruff in dummy.
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#7 User is offline   nige1 

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Posted 2021-January-25, 17:03

ManuDude03 'You are North on this hand and probably thinking the opps have gone mad when they bid 6. Partner, taking your double as lightner (asking for an unusual lead), leads the 4 which is won in dummy (declarer playing the 7). The 7 is then led from dummy, you duck (agree?), declarer wins the jack while partner plays the ten. Declarer then leads the 3 to which partner discards the 5 (encouraging). How do you defend?'
++++++++++++++++++++++++++
AL78 'Seeing both EW hands, why wouldn't declarer take a heart ruff before trying to draw trumps. They are down if the defender with the spade ace also held three diamonds and no more than two spades and leads a diamond for a ruff, but declarer is down whatever they do on that layout. It looks like declarer was playing for a defender with itchy fingers to try cashing an ace when in with the spade ace. That is the only chance I can see of a 12th tricks apart from a heart ruff in dummy.'
++++++++++++++++++++++++++
If s are 2-2 (as in the amended diagram on the left), then only a heart lead defeats 6. On any other lead, If declarer tries to ruff a in dummy, prematurely, then he snatches defeat from the jaws of victory. As the cards actually lay (with North holding 3s), ruffing a in dummy doesn't help declarer.

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#8 User is offline   gordontd 

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Posted 2021-January-25, 17:04

This reminds me of a ruling hand I had about 10 years ago. A pair had a long and complex relay auction to end up in 6S. The person on lead wondered which of his two aces he should try to cash. The answer was neither, the only defence to beat the slam was to lead his singleton trump to his partner's Ace after which partner needed to play another trump.

There was misinformation and the person on lead tried to argue that with the proper information he might have led a trump. I was not persuaded, having polled a few appropriate people.
Gordon Rainsford
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#9 User is offline   manudude03 

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Posted 2021-February-07, 13:21

View PostAL78, on 2021-January-25, 09:09, said:

Seing both EW hands, why wouldn't declarer take a heart ruff before trying to draw trumps. They are down if the defender with the spade ace also held three diamonds and no more than two spades and leads a diamond for a ruff, but declarer is down whatever they do on that layout. It looks like declarer was playing for a defender with itchy fingers to try cashing an ace when in with the spade ace. That is the only chance I can see of a 12th tricks apart from a heart ruff in dummy.


Declarer was simply playing for spades 2-2 or stiff ace (with no ruffs coming). If you ruff a heart early, what do you plan to do after (play a spade and North ducks)?
Wayne Somerville
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#10 User is offline   nige1 

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Posted 2021-February-07, 13:50

View Postgordontd, on 2021-January-25, 17:04, said:

This reminds me of a ruling hand I had about 10 years ago. A pair had a long and complex relay auction to end up in 6S. The person on lead wondered which of his two aces he should try to cash. The answer was neither, the only defence to beat the slam was to lead his singleton trump to his partner's Ace after which partner needed to play another trump.

There was misinformation and the person on lead tried to argue that with the proper information he might have led a trump. I was not persuaded, having polled a few appropriate people.
Here, is there a case for a weighed ruling? (In general, weighted rulings seem wrong to me). How does GordonTD respond to the argument that:
  • With the misinformation, the opening leader could never find the winning defence,
  • But with correct information, he would, at least, have had a chance, albeit small.



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#11 User is offline   mycroft 

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Posted 2021-February-07, 22:22

Yes, it could be. But not with the information Gordon found in the polling, I assume from what he wrote.

"Of course with the right information, you could have done the right thing. Oddly enough, though, the five people I asked all led an Ace without the misinformation, and when given the misinformation after, didn't think it would have affected the decision."

People come up with the most amazing rationalizations as to why they would have got it right after they know what's right. Frequently they're even reasonable justifications. When they are, they feel obvious. When they're not, one learns to be suspicious. Not throw it out, necessarily. But rely on unbiased polling over either their or our opinion with all the ex post facts.
When I go to sea, don't fear for me, Fear For The Storm -- Birdie and the Swansong (tSCoSI)
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#12 User is offline   pescetom 

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Posted 2021-February-09, 04:22

View Postmycroft, on 2021-February-07, 22:22, said:


People come up with the most amazing rationalizations as to why they would have got it right after they know what's right. Frequently they're even reasonable justifications. When they are, they feel obvious. When they're not, one learns to be suspicious. Not throw it out, necessarily. But rely on unbiased polling over either their or our opinion with all the ex post facts.

Although valid and unbiased polling is far from easy to achieve, both in terms of sample size (five is not enough, as statisticians have reminded us before) and bias induced by the phrasing of questions, or maybe even the sequence of questions (if I already said I would play an Ace, I might be less likely to decide otherwise now I have the correct information).
I have noticed that players polled often seem to be fishing for clues as to what I want to hear, which indicates how easily one could introduce bias. Recently I have also tried polling a group in a video conference and found it to be much harder to control than a group in presence would be.
I suspect that the best solution would be to poll a large group individually and simultaneously using appropriate software, preferably built into the play platform (although WhatsApp would be enough if it had native polling and that would work when playing in presence too).
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#13 User is offline   fromageGB 

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Posted 2021-February-11, 13:31

Puzzled at first, I realized it was a mahjongg hand!
The play goes anticlockwise.
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