[shyams]

World class players. Screens in use. Board not rotated -- i.e. North & East are screenmates.

E/W play a strong club system so a 1M opening is restricted to no more than 16 HCP
Alert 1: Alerted on both sides of the screen. Intermediate level jump overcall, at least 6-cards.
Alert 2: Alerted by West to South and explained as "Invitational raise with 4-card heart". When North asked East, explained as “Normally a forcing raise in hearts. In this situation, it is undiscussed”. North asks East if it shows 3-card or 4-card support, East says he is not sure.

North calls director and says that if the correct explanation was given, he would have considered bidding 4♠ instead of 3♠. Even over 4♥, with the right information, he would have found 4♠ as a sacrifice.

---

How would you rule?

Additional details for you, the TD:
1. If it matters, West asked South immediately about 2♠ before making the 2NT bid. East did not ask North for an explanation; the dialogue when the TD is called suggests East did not know 2♠ was “intermediate” during the bidding phase.
2. East claims only weak jump overcalls are alertable by North in WBF events. The alert of intermediate jump caused the subsequent confusion.
3. The same board was played on many other tables – if needed, the results of the other tables can be provided.

[Trinidad]

shyams, on 2015-October-17, 03:58, said:

2. East claims only weak jump overcalls are alertable by North in WBF events. The alert of intermediate jump caused the subsequent confusion.

I am not making a ruling yet, but I do want to point out that this claim is obviously nonsense and can easily be falsified: A jump overcall showing 4♠ and an unknown six card minor would definitely also have been alertable.

East's assumption that the jump overcall must have been weak may have caused the confusion, but this confusion was not due to North's alert. It was due to East not asking about the meaning of 2♠.

So, my question to East would be: "If you had known that 2♠ was intermediate, what would your explanation have been?". (And I would only point out to East that he was responsible for the confusion, if I would point that out at all, after I have this question answered.)

Rik

[Fluffy]

Perhaps I play on too many non perfect partnerships, but I think information north got (inv+ support) is pretty accurate.

[steve2005]

Only personal opinion for what its worth. Partner has intermediate jump you have 4♠, 10-card fit. Likely little wasted values in clubs and hearts.
I might not bid 4♠ right away, but over 4♥ I would be very worried that 4♠ might be making never mind a good sacrifice.

[shyams]

Fluffy, on 2015-October-17, 06:18, said:

Perhaps I play on too many non perfect partnerships, but I think information north got (inv+ support) is pretty accurate.

South got that information. North got the "fuzzy" explanation listed in the OP

[Trinidad]

In all MI cases, the first thing a TD should do is to establish what the correct information would have been.

So, was there an agreement about 2NT? If so, what was it? If not, what agreements were in place for similar situations?

Rik

[nige1]

A rule that might mitigate some such problems (assuming that players must explain in writing to screen-mates). At the end of the auction, before the opening lead, dummy passes his explanatory notes to declarer. If there's an agreement discrepancy, declarer must call the director ...

[weejonnie]

I think the phrase 'self-serving' is the politest I can come up with. North knows they have a 10-card spade fit and that the hearts are breaking (if not 2-2 then 3-2). North has based his calls on his (limited) defensive assets (JX QTX) and balanced hand. Those haven't changed. If West could have a 3-card heart suit then presumably they would be playing in a worse fit than with a 4-card suit. And why jump to 4♠ when the 2NT is 'invitational' only?

[aguahombre]

nige1, on 2015-October-17, 11:20, said:

A rule that might mitigate some such problems (assuming that players must explain in writing to screen-mates). At the end of the auction, before the opening lead, dummy passes his explanatory notes to declarer. If there's an agreement discrepancy, declarer must call the director ...

If dummy or declarer has expressed doubt during his explanation, he could stop the opening lead and what you suggest could then happen. I don't think it should be a routine to do so.

[paulg]

nige1, on 2015-October-17, 11:20, said:

A rule that might mitigate some such problems (assuming that players must explain in writing to screen-mates). At the end of the auction, before the opening lead, dummy passes his explanatory notes to declarer. If there's an agreement discrepancy, declarer must call the director ...

aguahombre, on 2015-October-18, 16:53, said:

If dummy or declarer has expressed doubt during an explanation, he could stop the opening lead and what you suggest could then happen. I don't think it should be a routine to do so.

In the ACBL, declarer and dummy are permitted to check with each other that the same explanations were given. This strikes me as sensible, preventing MI passing into the play.

However in the WBF, EBL, SBU, EBU, and (I guess) most other RAs this is explicitly forbidden. Indeed the WBF added a line to its screen regulations this year to confirm that this is not permitted. Their view is that no information is permitted to go across the screen and forbids the Director from doing it too.

[shyams]

weejonnie, on 2015-October-18, 13:59, said:

North knows they have a 10-card spade fit and that the hearts are breaking (if not 2-2 then 3-2). North has based his calls on his (limited) defensive assets (JX QTX) and balanced hand. Those haven't changed. If West could have a 3-card heart suit then presumably they would be playing in a worse fit than with a 4-card suit.

I think this is expressed the wrong way around. At the time East makes the 3♠ bid, if E/W are on a 5-3 fit, it becomes less important for North to stretch / sacrifice. It isn't hard for North to visualise hands where declarer loses a top spade, a trump and two diamonds.

weejonnie, on 2015-October-18, 13:59, said:

And why jump to 4♠ when the 2NT is 'invitational' only?

The 'invitational' explanation was not available to North; East told North something different.

[aguahombre]

paulg, on 2015-October-19, 01:07, said:

In the ACBL, declarer and dummy are permitted to check with each other that the same explanations were given. This strikes me as sensible, preventing MI passing into the play.

However in the WBF, EBL, SBU, EBU, and (I guess) most other RAs this is explicitly forbidden. Indeed the WBF added a line to its screen regulations this year to confirm that this is not permitted. Their view is that no information is permitted to go across the screen and forbids the Director from doing it too.

Interesting. Of course, Nige1 was suggesting a change to permit it; but out of curiosity -- what is the going penalty rate for correcting possible MI during the clarification period?