Year End C #7 - Swiss Pairs [MP>VP] - UI

[bluejak]

I do not understand this at all.  Just because it gets you to the same spot, why should it be disallowed?

Well, if the UI makes 3NT more likely to be the best spot, then I would think any call which is likely to get you to 3NT is suggested.

I don't. The UI suggests some sort of effort to avoid hearts at all costs, and 3♠ does not do that. It merely may be the best way to develop the hand.

[lamford]

On a spade lead, North has three lines:

(1) Ruff a spade high, draw trumps, play diamonds. The defence will be endplayed to provide a club entry when they win the second diamond (or the first club, if East has ♦A). That's playing for spades 3-3.

(2) Knock out ♦A, planning to throw a spade on a diamond before drawing trumps. Against best defence that needs diamonds 3-3 and no club ruff; declarer also needs to survive East's winning the second diamond and playing a club, which might prevent the later endplay.

(3) Draw trumps and play diamonds, then win the spade and use the endplay to obtain a club entry without letting East in. That needs West to have ♣AK and spades 2=6 or 1=7; again they might be able to prevent the endplay if East wins the diamond and plays a club.

 

I think that the third line is best, but only the first works on the actual layout.

 

<snip>

 

South also needs the rules explained to her.

 

Did EW do something egregious in defence to 3NT? Letting through a second overtrick looks bad, but I don't know if it's bad enough for them to forfeit any of their adjustment.

I agree with much of that, but actually think line 1, playing for hearts (not spades, being pedantic) 3-3 is the best. If you play a diamond at trick two, then you are really playing for a misdefence, as even your hoped for situation with West having all the minor cards is not good enough, as he ducks the first diamond, wins the next and plays a third diamond - and that is when clubs are 3-3.

 

I agree the weaker players will make Four Hearts more often - it is the intermediates that will fail (just teasing).

 

And I don't agree with either you or Frances on letting through 3NT+2. It is just careless. I am sure Frances would duck two diamonds and peer across at her partner's heart card on the third, when she would know whether to cash out. But not doing so is careless not egregious.

[gnasher]

I agree with much of that, but actually think line 1, playing for hearts (not spades, being pedantic) 3-3 is the best. If you play a diamond at trick two, then you are really playing for a misdefence, as even your hoped for situation with West having all the minor cards is not good enough, as he ducks the first diamond, wins the next and plays a third diamond - and that is when clubs are 3-3.

 

One of us is confused.

 

The line I favour is this one:

(3) Draw trumps and play diamonds, then win the spade and use the endplay to obtain a club entry without letting East in.

The line that involves playing a diamond at trick two is

(2) Knock out ♦A, planning to throw a spade on a diamond before drawing trumps. Against best defence that needs diamonds 3-3 and no club ruff; declarer also needs to survive East's winning the second diamond and playing a club, which might prevent the later endplay.

In line(2), if the defence win the second round of diamonds and play a third round, declarer throws a spade, draws trumps, and leads a club. As long as spades are 6-2, he is home.

 

And I don't agree with either you or Frances on letting through 3NT+2. It is just careless. I am sure Frances would duck two diamonds and peer across at her partner's heart card on the third, when she would know whether to cash out. But not doing so is careless not egregious.

And I don't agree with you that I said it was egregious.

[lamford]

And I don't agree with you that I said it was egregious.

I did not say that you did.

[gnasher]

And I don't agree with you that I said it was egregious.

I did not say that you did.

Then perhaps, for the sake of clarity, you can tell me which part of what I said you disagree with? Not that I mind being disagreed with, but I find it more agreeable to know what the specific areas of perceived disagreement are.

[lamford]

And I don't agree with you that I said it was egregious.

I did not say that you did.

Then perhaps, for the sake of clarity, you can tell me which part of what I said you disagree with? Not that I mind being disagreed with, but I find it more agreeable to know what the specific areas of perceived disagreement are.

Letting through a second overtrick looks bad, but I don't know if it's bad enough for them to forfeit any of their adjustment.

 

That is the sentence with which I disagreed; and I disagreed with Frances that it was normal. I think that even thinking about forfeiting any of the adjustment is an error, and I think that the true assessment of the defensive error was about half way between your "looks bad" and Frances "normal".

[lamford]

I now think the right line in 4H is very close indeed, and have a few more comments.

 

The chance of the 3-3 heart break has dropped to 7/18*6/17*5/16*11/15*10/14*9/13*COMBIN(6,3) which I make 31%, so this seems to be the rough chance of playing for hearts 3-3. This chance goes up when you require West to have at least one of the minor-suit honours - to around 34%.

 

I still do not understand your line 2. West would only play a third diamond if East is ruffing, and therefore you cannot throw a spade on this trick.

 

I now believe I underestimated your line 3; if West has the ace, king of clubs, you make regardless of where the ace of diamonds is, whether or not East plays a club through. The chance of West having both these cards is around 36% (11/18*10/17). However, some of these times the defence might have found a club ruff (when East has a doubleton).

 

When West has all three minor-suit honours, however, the 3-3 heart break has gone up to 39%, and when he has two, it is around 36.5%, so line 1 is back in front again. Add in the fact that hearts 5-1 will trim something off drawing trumps immediately (but not off ruffing a spade high, as that is already considered). Also many Easts would not overcall 2S with just QJxxxx and out.

 

Tough call, but my best guess is:

 

Line 1 36%

Line 2 pretty small

Line 3 32%

 

But I am sure that those who are better at maths than me can work it all out more accurately.

[lamford]

I do not agree with people in this thread who think 3♥ shows very good hearts particularly, nor did I believe 3♠ was disallowed, so eventually I ruled

   40% of 3NT +2, NS +460

+ 45% of 4♥=, NS +420

+ 15% of 4♥ -1, NS -50

 

Both sides seemed happy enough.

A reasonable job, except I would give some percentage of 3NT + 1 (different declarer, as Jallerton explains).

 

The other issue is that South did not "carefully avoid taking advantage of the UI" by her own admission. Her honesty is to be congratulated, but is 3S conforming to this law? If it is not, then one might impose your 3:1 ratio of 4H making without the 3NT part.

[gnasher]

The chance of the 3-3 heart break has dropped to 7/18*6/17*5/16*11/15*10/14*9/13*COMBIN(6,3) which I make 31%, so this seems to be the rough chance of playing for hearts 3-3. This chance goes up when you require West to have at least one of the minor-suit honours - to around 34%.

It's lower than that, because we can be fairly sure that East doesn't have a singleton in a minor. That may affect the chances for the other lines as well, of course.

 

I still do not understand your line 2. West would only play a third diamond if East is ruffing, and therefore you cannot throw a spade on this trick.

Yes. That's why I said "(2) ... needs diamonds 3-3". Line (2) is clearly inferior to the others, but is also what someone might choose instinctively.

 

I now believe I underestimated your line 3; if West has the ace, king of clubs, you make regardless of where the ace of diamonds is, whether or not East plays a club through.

East wins the second diamond and plays a club to the queen and king. West exits with his remaining spade and waits to score ♣A10.

 

When West has all three minor-suit honours, however, the 3-3 heart break has gone up to 39%, and when he has two, it is around 36.5%, so line 1 is back in front again.

You can't do that, can you? You have already included the cases where West had three hearts and both club honours in your 31% or 34% for a 3-3 break.

 

Also many Easts would not overcall 2S with just QJxxxx and out.

Possibly true, but let's not overstate this effect. It could be as good as QJ108xx.

[lamford]

The chance of the 3-3 heart break has dropped to 7/18*6/17*5/16*11/15*10/14*9/13*COMBIN(6,3) which I make 31%, so this seems to be the rough chance of playing for hearts 3-3. This chance goes up when you require West to have at least one of the minor-suit honours - to around 34%.

It's lower than that, because we can be fairly sure that East doesn't have a singleton in a minor. That may affect the chances for the other lines as well, of course.

 

I still do not understand your line 2. West would only play a third diamond if East is ruffing, and therefore you cannot throw a spade on this trick.

Yes. That's why I said "(2) ... needs diamonds 3-3". Line (2) is clearly inferior to the others, but is also what someone might choose instinctively.

 

I now believe I underestimated your line 3; if West has the ace, king of clubs, you make regardless of where the ace of diamonds is, whether or not East plays a club through.

East wins the second diamond and plays a club to the queen and king. West exits with his remaining spade and waits to score ♣A10.

 

When West has all three minor-suit honours, however, the 3-3 heart break has gone up to 39%, and when he has two, it is around 36.5%, so line 1 is back in front again.

You can't do that, can you? You have already included the cases where West had three hearts and both club honours in your 31% or 34% for a 3-3 break.

 

Also many Easts would not overcall 2S with just QJxxxx and out.

Possibly true, but let's not overstate this effect. It could be as good as QJ108xx.

 

OK I agree that we can refine that 36.5% a bit; it would take too long to consider all excluded distributions, but if we force West to have two minor suit honours, then there are fewer available spaces for hearts, so we are right, I think, to adjust the 3-3 heart break upwards. So around 34% for 3-3 hearts seems about right.

 

Back to line 2 again. If diamonds are 3-3, surely there is a club ruff around, or the hearts are 5-1 if there is some lucky blockage in clubs. No, I still can see little merit in this line.

 

Yes, if East has the ace of diamonds, he will play a club through, and you either have to play him for a club honour or the ten of clubs. So your line 3 drops quite a bit on your correct analysis of this situation. So, in summary, you need either all three honours with West, or both the ace, king of clubs and not the ten. You can never make it when East has two minor suit honours, so you may as well guess to put in the nine when he plays a club.

 

However, this merely drops your line 3 to below 30% (you will never make a politician, you are too honest) and I now think it is not so close after all.

[greenender]

Without meaning any disrespect to Andy or Paul, I'm not sure that detailed discussions of the best line in 4♥ add much to a Laws & Rulings forum.

 

I'd be happy with a conclusion that the ruling should contain an X% weighting for a 4♥ contract, making however many tricks it's due to make, further weighted between various possible outcomes (i.e. numbers of tricks) as appropriate.