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Lead Problem H - MSC August T4 K83 J43 AT843 against 1nt-2C-2S-3S-4S

Poll: Lead Problem H - MSC August (18 member(s) have cast votes)

Your lead at the table?

  1. ST (3 votes [17.65%] - View)

    Percentage of vote: 17.65%

  2. S4 (3 votes [17.65%] - View)

    Percentage of vote: 17.65%

  3. HK (0 votes [0.00%])

    Percentage of vote: 0.00%

  4. H8 (1 votes [5.88%] - View)

    Percentage of vote: 5.88%

  5. H3 (1 votes [5.88%] - View)

    Percentage of vote: 5.88%

  6. DJ (0 votes [0.00%])

    Percentage of vote: 0.00%

  7. D4 (0 votes [0.00%])

    Percentage of vote: 0.00%

  8. D3 (7 votes [41.18%] - View)

    Percentage of vote: 41.18%

  9. CA (2 votes [11.76%] - View)

    Percentage of vote: 11.76%

  10. CT (0 votes [0.00%])

    Percentage of vote: 0.00%

  11. C8 (0 votes [0.00%])

    Percentage of vote: 0.00%

  12. C4 (0 votes [0.00%])

    Percentage of vote: 0.00%

  13. C3 (0 votes [0.00%])

    Percentage of vote: 0.00%

What you think will be the best lead, if everyone plays double dummy after the lead?

  1. ST (4 votes [23.53%] - View)

    Percentage of vote: 23.53%

  2. S4 (3 votes [17.65%] - View)

    Percentage of vote: 17.65%

  3. HK (0 votes [0.00%])

    Percentage of vote: 0.00%

  4. H8 (0 votes [0.00%])

    Percentage of vote: 0.00%

  5. H3 (1 votes [5.88%] - View)

    Percentage of vote: 5.88%

  6. DJ (0 votes [0.00%])

    Percentage of vote: 0.00%

  7. D4 / D3 (3 votes [17.65%] - View)

    Percentage of vote: 17.65%

  8. CA (6 votes [35.29%] - View)

    Percentage of vote: 35.29%

  9. CT (0 votes [0.00%])

    Percentage of vote: 0.00%

  10. C8 (0 votes [0.00%])

    Percentage of vote: 0.00%

  11. C4 / C3 (0 votes [0.00%])

    Percentage of vote: 0.00%

What do you think will be the 2nd best lead, double dummy (if you voted for touching cards for 1st best, choose a different answer here)

  1. ST (5 votes [29.41%] - View)

    Percentage of vote: 29.41%

  2. S4 (2 votes [11.76%] - View)

    Percentage of vote: 11.76%

  3. HK (0 votes [0.00%])

    Percentage of vote: 0.00%

  4. H8 (0 votes [0.00%])

    Percentage of vote: 0.00%

  5. H3 (4 votes [23.53%] - View)

    Percentage of vote: 23.53%

  6. DJ (0 votes [0.00%])

    Percentage of vote: 0.00%

  7. D4 / D3 (3 votes [17.65%] - View)

    Percentage of vote: 17.65%

  8. CA (2 votes [11.76%] - View)

    Percentage of vote: 11.76%

  9. CT (0 votes [0.00%])

    Percentage of vote: 0.00%

  10. C8 (0 votes [0.00%])

    Percentage of vote: 0.00%

  11. C4 / C3 (1 votes [5.88%] - View)

    Percentage of vote: 5.88%

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#1 User is offline   Mbodell 

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Posted 2015-July-12, 23:53

IMP all red


5 different cards chosen by panelists, close to even 4 way split among both panelists and solvers for the top lead.
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#2 User is offline   mikeh 

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Posted 2015-July-13, 09:33

I think this is pretty much a guess.

About the only suit I would rule out would be diamonds. Jxx is an awful lead, requiring specific holdings to gain a trick and often blowing one, as well as blowing a tempo, tho when the opps strain to bid game after a 1N, tempo is not as important as it usually is.

I can see the case for a spade, but on this auction the trump may not be the passive lead we were playing to make. There are a lot of holdings where leading from 10x picks up the suit for declarer.

The heart suit is what I would lead....I would lead low. This can blow up as well, but my experience with these leads has been generally pretty good. Leading from a short K when the Ace rates not to be in dummy often gains immediately and, when it doesn't, often ends up not costing a trick...imagine dummy with J10xx and declarer AQx.

Clubs...we can lead the Ace and hope to catch a stiff in partner's hand, or we can lead low, hoping for good things either now (partner with Kx for example, or the K in dummy and partner with the Q, or partner with a doubleton and a trump entry, but to me all of these are low percentage, and not assured to win....will partner, with xx in clubs, always win his trump and return clubs?

I probably underlead Kings more than most people, so I suspect I am biased here, but the heart is, to me, the best lead.

Frankly the other options don't interest me: I don't ever think that way at the table, and I don't think that double dummy assumptions are ever warranted in the actual game.
'one of the great markers of the advance of human kindness is the howls you will hear from the Men of God' Johann Hari
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#3 User is offline   Jinksy 

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Posted 2015-July-13, 15:10

I will be quite surprised if the club ace doesn't win DD. Perfect players love not having a human throw away their control of the hand.

At the table I agree with mikeh that it's a guess, but I pretty much have the reverse preference:

A heart is my last choice - I barely registered it as an option after first glance.

ATxxx has too much chance of blowing the suit wide open for my limited capacity to find the killer switch after seeing dummy. Better players than me would prob do better from it.

Leading a S probably won't do much to cut down on ruffs in a 4-4 hand, and has a 3/10 chance of picking up partner's queen (and a little extra of carving a K holding since I have the 10).

I don't like leading from Jxx much more than mikeh, but it feels less likely to give away a trick they couldn't pick up anyway than any of the others.
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#4 User is offline   wank 

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Posted 2015-July-13, 16:48

diamond seems like the boring obvious choice. ace of clubs to give partner a ruff if you're aggressive (yeah you have the option of switching but absent cheating you'll have no idea whether partner is ruffing or not)
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#5 User is offline   Phil 

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Posted 2015-July-13, 19:40

I checked my answers - I led the 3.

Far from convinced this is the best choice.
Hi y'all!

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#6 User is offline   gnasher 

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Posted 2015-July-14, 02:35

View PostJinksy, on 2015-July-13, 15:10, said:

Leading a S probably won't do much to cut down on ruffs in a 4-4 hand, and has a 3/10 chance of picking up partner's queen (and a little extra of carving a K holding since I have the 10).

3/10 is the probability that partner has any 3-card holding including the queen, given that all we know is that he has three cards. However, that's not the probability of picking up his queen.


To calculate the actual probability of picking up partner's queen you have to exclude layouts where declarer was going to finesse it anyway, and the layouts where partner's holding is strong enough to survive the lead. That means you have to exclude layouts where:

- Declarer has the jack
- Dummy has AKJ
- Partner has the jack
- Partner has the king and there was an intrafinesse
- Partner has 98
- Partner has the nine and dummy has HJ

Furthermore, we're expecting partner to have about 7/32 of the outstanding high-card strength. The probability has to be reduced to reflect that expectation.

I'd guess that the actual chance of picking up partner's queen is in the 2-3% range.

... 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   the_clown 

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Posted 2015-July-14, 03:16

I would lead a diamond hoping not to blow a trick. A is close second.
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#8 User is offline   gordontd 

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Posted 2015-July-14, 03:43

View Postthe_clown, on 2015-July-14, 03:16, said:

A is close second.

Maybe even first choice, if you held the card.
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#9 User is offline   PhilKing 

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Posted 2015-July-14, 03:57

View Postgnasher, on 2015-July-14, 02:35, said:

3/10 is the probability that partner has any 3-card holding including the queen, given that all we know is that he has three cards. However, that's not the probability of picking up his queen.


To calculate the actual probability of picking up partner's queen you have to exclude layouts where declarer was going to finesse it anyway, and the layouts where partner's holding is strong enough to survive the lead. That means you have to exclude layouts where:

- Declarer has the jack
- Dummy has AKJ
- Partner has the jack
- Partner has the king and there was an intrafinesse
- Partner has 98
- Partner has the nine and dummy has HJ

Furthermore, we're expecting partner to have about 7/32 of the outstanding high-card strength. The probability has to be reduced to reflect that expectation.

I'd guess that the actual chance of picking up partner's queen is in the 2-3% range.


But it can also pick up his king, or turn KJx, AJx, KQx and AQx into one trick.
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#10 User is offline   gnasher 

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Posted 2015-July-14, 13:23

View PostPhilKing, on 2015-July-14, 03:57, said:

But it can also pick up his king, or turn KJx, AJx, KQx and AQx into one trick.


I intended AQx and KQx to be included in my 2-3%, but anyway I agree that these are all reasons not to lead a trump. I was just nitpicking Jinksy's calculation, rather than actually advocating a trump lead (though it is what I'd lead).
... 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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#11 User is offline   Jinksy 

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Posted 2015-July-15, 12:05

View Postgnasher, on 2015-July-14, 02:35, said:

3/10 is the probability that partner has any 3-card holding including the queen, given that all we know is that he has three cards. However, that's not the probability of picking up his queen.


To calculate the actual probability of picking up partner's queen you have to exclude layouts where declarer was going to finesse it anyway, and the layouts where partner's holding is strong enough to survive the lead. That means you have to exclude layouts where:

- Declarer has the jack
- Dummy has AKJ
- Partner has the jack
- Partner has the king and there was an intrafinesse
- Partner has 98
- Partner has the nine and dummy has HJ

Furthermore, we're expecting partner to have about 7/32 of the outstanding high-card strength. The probability has to be reduced to reflect that expectation.

I'd guess that the actual chance of picking up partner's queen is in the 2-3% range.


Well sure, but by 'picking up' I mean 'effectively solving for declarer on the lead', not doing something he couldn't theoretically do himself. In many such situations his options for playing the hand will then then give him fewer opportunities to go wrong elsewhere. If we knew the actual probabilities of it giving something away and of (say) a small diamond doing the same, we wouldn't have a lead problem.
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#12 User is offline   Jinksy 

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Posted 2015-July-15, 12:06

View Postgordontd, on 2015-July-14, 03:43, said:

Maybe even first choice, if you held the card.


There's an important space in the the_clown's sentence that you haven't credited him with.
The "4 is a transfer to 4" award goes to Jinksy - PhilKing
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#13 User is offline   Thiros 

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Posted 2015-July-15, 12:50

I led 4. E-W have not bid as though their hands can make 4NT. It is unlikely that declarer's play plan will involve drawing trumps early. Note that this is not a domineering consideration but tips the balance only in light of the fact that leading from the other holdings is relatively unappealing. Change the hearts to QJ10 and I am a heart leader (I think). Leading the 10 would be easier on partner but I see tangible benefit in retaining the 10 here. Suppose there is four of a red suit in dummy and two of that suit in declarer's hand; if he tries for two ruffs of that suit in his hand, our 10 may create a complication for the offense when dummy leads the fourth round.
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#14 User is offline   nige1 

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Posted 2015-July-15, 13:03

View PostMbodell, on 2015-July-12, 23:53, said:



IMP all red
5 different cards chosen by panelists,
close to even 4 way split among both panelists and solvers for the top lead.
I rank

  • Passive. John Mclaren called trumps "The Idiot's lead". Lead the ten not the four.
  • Aggressive. Might set up a trick before loser cab be discarded on dummy's club.
  • Wishy-washy. Usually passive but might set up a trick.
  • The sight of dummy may suggest something

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#15 User is offline   cherdano 

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Posted 2015-July-15, 20:49

I really dislike the heart lead given that declarer denied length in the suit. Lead from the king is most dangerous when declarer has a doubleton, and the odds of that have gone up quite a bit when he denied a 4-card heart suit.
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#16 User is offline   mike777 

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Posted 2015-July-15, 22:36

View Postcherdano, on 2015-July-15, 20:49, said:

I really dislike the heart lead given that declarer denied length in the suit. Lead from the king is most dangerous when declarer has a doubleton, and the odds of that have gone up quite a bit when he denied a 4-card heart suit.


interesting

I would have lead a h, aggressive as a nonexpert....ty for post.
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#17 User is offline   PhilKing 

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Posted 2015-July-16, 06:26

These days, the very top players virtually never lead away from a king on an auction like this.

The lead of a heart might score OK in the Bridge World, but that is because although times have changed, the panel contains a lot of octogenarians who are used to a far more aggressive style of leads.
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#18 User is offline   Zelandakh 

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Posted 2015-July-16, 06:35

View Postmikeh, on 2015-July-13, 09:33, said:

The heart suit is what I would lead....I would lead low.


View PostPhilKing, on 2015-July-16, 06:26, said:

The lead of a heart might score OK in the Bridge World, but that is because although times have changed, the panel contains a lot of octogenarians who are used to a far more aggressive style of leads.

Ouch! :blink: For what it is worth I was also surprised Mike went for the heart.
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#19 User is offline   PhilKing 

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Posted 2015-July-16, 06:45

View PostZelandakh, on 2015-July-16, 06:35, said:

Ouch! :blink: For what it is worth I was also surprised Mike went for the heart.


I'll get my coat.
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#20 User is offline   mikeh 

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Posted 2015-July-16, 08:04

View PostPhilKing, on 2015-July-16, 06:26, said:

These days, the very top players virtually never lead away from a king on an auction like this.

The lead of a heart might score OK in the Bridge World, but that is because although times have changed, the panel contains a lot of octogenarians who are used to a far more aggressive style of leads.

Well, it isn't as tho we have a purely passive lead on the hand. Had my spades been even a tad worse, I would have led one in a heartbeat. Were my diamonds lacking the J, that would have been an easy choice as well. IMO, all of the lead options were dangerous, which is presumably why it was seen as a good problem. The fact that 'the very top players virtually never lead away from a king' on this type of auction doesn't impress me very much, because on virtually all auctions like this, we will have at least one lead that seems far safer than leading away from the king. Fwiw, I would not lead from the king here if I held 4 or more in the suit, since that would slightly increase the chances of the most dangerous declarer holding...a doubleton with his side holding the A and the Q. I think I'd lead a spade then.

So, while I am not even close to being one of the very top players, I would 'virtually never lead away from a king on this auction' either :P it's merely that when all leads are bad, this time the heart seems to me to be the best of a bad bunch.
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