Bridge: 2021 MSC Discussion

The Sandbox Games
82 
                       A     B     C         D     E     F     G     H
procrastinator        2S   Dbl     P    2D; 4C    3C     P     P   D10
SW                    2S     P     P    2D; 4H    2N    3D   Dbl    CA
ST                    2S     P     P    2D; 4H    3C     P   Dbl    S8
BTDT                  2S   Dbl     P    2D; 4H    3C     P     P    S8
NN                                                                    
veni vidi vici        2S     P     P    2D; 4C    3H     P     P    CA
Abstract Actuary      2S   Dbl     P    2D; 4N    3H    3H    2S    CA

Leading               2S           P    2D; 4H    3C     P     P    CA

Leaders on all except one, which is tied 3-3. Maybe we’ll get a vote from Numbers Nerd, and I also asked 4Sigma, who used to participate on the AO.

83

Very hard to judge the probabilities of various outcomes. But with 7H in the mix, there are some special complications.

If the hand is a “5 or 7” hand, you don’t want to bid 6 (Unlikely you would know during the bidding, but as a theoretical issue. And on some deals you might know during the bidding.)

E.g. suppose partner’s hand is Ax Axx KQxxx Qxx. This is not a pure “5 or 7” but it’s pretty close if the opponents will find a spade lead. If you don’t lose a heart, you’ll make 7. If you do lose a heart (and they led a spade), you won’t even make 5. So 7 is the better contract, losing only an extra 50 points if it doesn’t make.

OTOH, except for “5 or 7” hands, you don’t want to bid 7, even if it’s a favorite, if there’s any significant chance other tables will stop in below slam. Vs a pair who stops in 4H or 5H, the payoff table works:

If 11 tricks make, you are +0 imps if you stop below slam, -500 points (-11 imps) if you bid 6, -550 points (still 11 imps) if you bid 7.

If 12 tricks make, you are +0 if you stop below slam, +500 (+11 imps) if you bid 6, -530 (-11 imps) if you bid 7.

If 13 tricks make, you are +0 if you stop at game, +500 (+11 imps) if you bid 6, +750 (13 imps) if you bid 7.

In other words, compared to any table that stops below game, you gain a maximum of 2 imps for bidding 7 instead of 6. Terrible odds if there’s significant chance that exactly 12 tricks will make.

84

4Sigma’s thoughts, which will break the tie in favor of double on B unless we hear from NN or someone else.

85

Interesting dynamic that I was not aware of. So at IMPs, never bid to 7, unless it is a “5 or 7” hand? I’ll have to try to wrap my head around what a 5 or 7 would be a little better. Is that only when not vulnerable? Or the same dynamic applies when vulnerable?

86

It is rare that you would ever recognize a 5-or-7 hand in the bidding, but possible.

As for bidding 7 otherwise, that argument against bidding 7 only applies if there is significant chance of other tables not in 6. If everyone is bidding at least 6, I don’t remember the break-even point (could figure it out by the gain / loss), but it’s around 50%. I think you would prefer to avoid a 50% grand if you knew the other table (in a team match, which imps usually are) would be in 6 or 7, but you don’t need much better than 50%, and would not be upset if you bid a 50% grand. It’s only if you might have already won most of the imps by reaching any slam.

Vul doesn’t matter a lot.

87

I once recognized a 5 or 7 hand in the bidding. (It was a cross-ruff hand, and if they ever overruffed they could lead a second round of trump and hold it to 11 tricks.) So I bid 7, got the expected trump lead, guessed right what to ruff high and what to ruff low, and made it. My partner was furious that I had bid 7, and when I pointed out that I knew it was a 5 or 7 hand, he said “Yeah, but do you really think they would lead trumps against 6?”

88

I’ve been rethinking B, D, and G. I’m changing my votes on D and G and explaining my reason for not doing so on B.

On B, partner is likely to pass the double, since we know he has four spades. It’s just too likely 1S is making anyway. I think spades are likely 6-2. Partner probably has a weak NT. It won’t be shocking for declarer to have 5 trump tricks and the AK of hearts, and dummy’s doubleton trump won’t take a ruff, but it will prevent us cashing 6 minor-suit winners before declarer gets his discard. Of course, declarer’s spades may be somewhat worse but there’s plenty of room for the opps to have one minor-suit trick in that case, or even two. If my hearts were KJxxx rather than QJxxx, my hand would be worth almost a full trick more on defense. Then I’d double. Here I pass.

On D, after thinking about it, I don’t think I should splinter given the C QJx is worth more than the S QJx. I was worried about spades, but I don’t think partner is likely to move with no spade control given he hasn’t got the minor-suit aces, either. So I’m changing to 2D;4H.

On G, I’m having trouble imagining declarer coming to eight tricks on a trump lead unless he has AKQxx Axxxx and a fast entry in the form of a void or a side ace. A side ace is possible but unlikely. A void is at best 22% and probably less. Note again how KJ length in the opponents’ side suit is much better than QJ length. I wouldn’t hit this at IMPs, especially as partner is limited by his failure to double (given that I doubled 2C, he’s probably limited to 13 highs or so), but we do seem to be a favorite to beat 2H, so I’m doubling.

89

Note that this may change the leader on both B and G.

90 
                       A     B     C         D     E     F     G     H
procrastinator        2S   Dbl     P    2D; 4C    3C     P     P   D10
SW                    2S     P     P    2D; 4H    2N    3D   Dbl    CA
ST                    2S     P     P    2D; 4H    3C     P   Dbl    S8
BTDT                  2S   Dbl     P    2D; 4H    3C     P     P    S8
NN                                                                    
veni vidi vici        2S     P     P    2D; 4H    3H     P   Dbl    CA
Abstract Actuary      2S   Dbl     P    2D; 4N    3H    3H    2S    CA

Submitted             2S   Dbl     P    2D; 4H    3C     P   Dbl    CA
91 
                  A          B        C        D            E        F        G        H        Total
procrastinator    2S     100 Dbl  50  P    90  2D; 4C   100 3C   100 P    90  P    90  D10  50  670  
SW                2S     100 P    40  P    90  2D; 4H   90  2N   40  3D   50  Dbl  100 CA   80  590  
ST                2S     100 P    40  P    90  2D; 4H   90  3C   100 P    90  Dbl  100 S8   100 710  
BTDT              2S     100 Dbl  50  P    90  2D; 4H   90  3C   100 P    90  P    90  S8   100 710  
veni vidi vici    2S     100 P    40  P    90  2D; 4H   90  3H   40  P    90  Dbl  100 CA   80  630  
Abstract Actuary  2S     100 Dbl  50  P    90  2D; 4N   70  3H   40  3H   30  2S   60  CA   80  520  
Submitted         2S     100 Dbl  50  P    90  2D; 4H   90  3C   100 P    90  Dbl  100 CA   80  700  


                                                                                     
                  2S     100 1NT  100 3C   100 2D; 4C   100 3C   100 Dbl  100 Dbl  100 S8   100   
                             Dbl  50  P    90  2D; 4H   90  3H   40  P    90  P    90  CA   80       
                             P    40           2D; 4N   70  2N   40  3D   50  2S   60  D10  50       
                                                                     3H   30

We sure missed the boat on B. Tough time deciding between P and Dbl, when neither was worth more than 50. I don’t put actions none of us took, except the top choice, in the scoring table, but 1NT got 12 panel votes and 2C got 10. Dbl got only 5 and P got 4.

The scoring was a little strange on both C and D, with only 10 points controversial on each. Both of those were exactly tied among the panel for the top two choices. Both had a very clear preference among the solvers: over 50% for one action; under 30% for the other. In both cases, the action the solvers rejected was given 100; the other, 90.

Congratulations to ST and BTDT for our top scores of 710. The consensus at 700 also made the honor roll (700 was the minimum honor roll score)

92

July contest. Deadline May 31. As always, I hope to enter before the last minute.

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93

What does 1NT even mean here? I never considered it, but it has to be some convention I forgot or never knew about. Completely unnatural.

94

First crack.

A: 3H. I am sure I will not do well here, because I’m mostly making this up. But Partner presumably has the high end of the passing range, and at least decent spades. But probably only 4, because otherwise he could have bid 2S for cheap. So 8-12 points, 4 spades. Now I have a lot of strength. I considered 3C to show my club length, but it does not show enough power. I considered 2NT, as an artificial show of strength (not positive that’s what it means). I considered 2S, but likely undersells my strength. 3S, oversells my spade strength. 4C advances us too far.

B: 2C. With them vulnerable, and everyone east appearing weak, I’ll make a balancing overcall. With unfavorable vulnerability, I think I would have passed.

C: P. Seems likely we don’t have high potential. Any bid feels like it could get us into trouble.

D: 3D. Seems a tough spot. 2S or 3C as lead-directional has some value if they are going to end up in 3NT, but does not seem worth the negatives. 3D as a further preemptive bid.

E: 3S. Let’s give us a chance to find this game in major.

F: 3D. I’m going to try the cue bid again. Again partner may have 4 spades, we have a strong 3 spades. And are at the high end of our range. Making a spade raise marginal. So using the cue bid to show strength. This feels a lot like problem A.

G: 5H. Tough one. Was leaning pass. But there is a very good chance they have a spade game here, so it’s part sacrifice and part preemptive. And there’s an outside chance we make it if partner has the perfect hand.

H: P, CK. I’m a little unsure what partner’s double means. Presumably it is a lead directing double, but I couldn’t find much in the notes. So would appreciate a bit of help here. I think it calls for an unusual lead, so not clubs. But he may be saying that because he knows he doesn’t have the AK of clubs? And if he doesn’t want me to lead clubs, and presumably not trump, then I’m not sure what I would pick. The S6?

95

I can’t be sure since I don’t have the physical magazine with explanations yet, but I expect it will say that it is completely natural, that Partner must have some spades since he didn’t act and East didn’t raise

96

Interesting. That feels like a bit of a leap. But maybe at 1NT not as big of a risk to lose all the tricks in a suit.

97

July guesses:

A: Double. Is this problem allowed in MSC? There are supposed to be at least 3 calls, and here Double and Pass are the only reasonable ones, given that my clubs are too ratty to rebid. Stiff HK argues for defending, but neither at matchpoints argues that I will likely be defending 3H if I balance, so Double for me.

B. 1S. Partner isn’t likely to get overexcited, since this is a passed hand. 2C may be fine if the auction keeps going, but there seems to be a good chance I’d play it right there for an inferior matchpoint score when we belong in spades.

C 3D. At some point I’m strong enough to just bid my hand. Close second choice: 2S to keep the auction open. I could be convinced.

D 4D. I don’t like to make lead directing bids when I’m not sure which suit I want led. Especially as I have pretty much taken them out of bidding NT, so the only diamond suit partner is likely to make a disastrous lead from is K109xxx with no side singleton. I’ll pay off to that in order to put the pressure on. The other problem with a lead direct is it may make LHO feel safer about coming in to the auction with a weak hand and hearts (which we pretty much know is what he has). 3H by them rates to be a wonderful contract, so I don’t mind jumping to 4D here.

E 3S. Huge overbid, but no other bid gets us to the right strain anywhere near as often.

F 3NT. Hamman’s rule. And make West lead away from his stuff. I wish I could bid 3D, but the tray is likely to come back with the 4C card on it when 3N was right and 4-major fails. If West can find underleading two high honors, I will congratulate him if this is at the table, but report suspicions if this is on-line.

G 5H. This is a classic rock/paper/scissors problem. If I bid 5D, LHO can cue 5H with his heart void and they can find a slam when they would have played 5S over 5H. If I bid 5H, and cue-bidder is 5=0=3=5, they’ll ruff the opening lead vs 5S when DtoAKruff would set them. If I bid 6D, they defend 6HX for 500 when we had three cashers. I don’t think LHO is strong enough to cue 6H over 6D, so there isn’t much advantage to bidding 6H. Unfortunately, 6D has a problem I haven’t mentioned yet…partner may take it something more like KQJxxx and hearts support, and may take a phantom save if they bid 6S (since it’s a JUMP in a new suit, it sounds like it’s asking for his cooperation). At matchpoints, I’d probably bid some number of diamonds. The lead would be important more often (those pesky 30 point overtricks matter at matchpoints), and partner would be much less likely to sacrifice at matchpoints.

H Pass|D3. Even if I don’t think I can set this (because after partner ruffs the opening lead someone is probably ruffing the club return), 6HX is less costly than 7D making on the now marked finesse.

98

A) 3C
B) 1S
C) Pass
D) 3C
E) 3S
F) 3D
G) 5H
H) Pass then D3

99

A) 2S, matchpoint fever
B) Pass. 1S close second.
C) 2S - thought this was pretty standard
D) 3D. Since i am happy with any lead, just a straightforward raise
E) 3S. Obviously pushy, but passing is scary
F) 3NT, perhaps foolhardy, Hx with RHO somewhat likely
G) 5D - not sure this shows a fit, but I really want a diamond lead against 5S.
H) Pass, diamond three (edit, had led top club before realizing from other replies that partner had doubled)

100 
                       A     B     C         D     E     F     G     H
procrastinator        2S     P    2S        3D    3S    3N    5D P; D3
SW                    2S    1S    2S        2S    3S    2N    5D P; D3
ST                    3H    1S    2S        3C   Dbl    3N    5D P; D3
BTDT                  3C    1S     P        3C    3S    3D    5H P; D3
NN                                                                    
veni vidi vici       Dbl    1S    3D        4D    3S    3N    5H P; D3
Abstract Actuary      3H    2C     P        3D    3S    3D    5H P; CK

Leading                     1S    2S              3S    3N       P; D3

My answers (and Sweet Tooth’s, sent by e-mail) are included in the table. Three still tied, and unless I hear from NN tomorrow, I’ll have to guess something.

101

I was going too fast with my initial thoughts, especially as I included an inadmissible call. So I ended up changing my votes on four problems: I think this resolves all the ties, too.

I realized I misread A. I thought partner had passed. Given that he doubled, obviously I can’t double, and it’s close between 2S and 3H. I am going with 3H because I judge it likely partner is either 5=5 or 4=6 in the unbids (it seems unlikely he has enough high cards to justify doubling with 4=3=5=1), and we figure to make 4 of the correct suit.

On C I am prepared to admit that 3D was going a bit far and am changing my vote to 2S, as I noted initially I might do.

On D I wonder whether 2H or 3H will help partner find a trump lead against 4H. :slight_smile: Anyway, the real decision is between 3D and 4D. You bid 4D if you want to pressure them into bidding 4H and then setting it. You bid 3D if you want to make invitational sequences difficult and hopefully just defend 3H. Given that it’s IMPs, pushing them to game when I am aceless is probably the bigger risk, so I am changing my vote to 3D.

On G I think it’s extremely close between 5D and 5H. I’m starting to think that the value of 5D in helping partner may actually be worth more than the extra auction space it gives the opponents. So changing my vote to 5D.

On H I don’t understand the vote for the club lead. When you are right it saves at best 5 IMPs vs the other lead, and you would have done better to have bid 7C. When you are wrong it loses either 7 IMPs or 18 IMPs to the diamond lead. The choice here is between leading the smallest diamond and bidding on. Despite the vote, it’s actually pretty close. The reason I pass is that we could still be setting this on the diamond lead when partner has a slow spade trick, even if doubler is void of clubs. (Yet another reason not to lay down a high club on opening lead.) This is a really funny problem at rubber bridge, where you should definitely bid 7C if your partner is the best player at the table.

My new votes:
3H
1S
2S
3D
3S
3N
5D
P|D3