campboy

Because 47E says there is no further rectification. In the case of an OLOOT, Law 54 is the rectification in question that there is no of. If 47E didn't supersede the laws governing rectification of leads/plays out of turn, it would be completely pointless.

Nope.

Thanks. It looks like the non-uniformity of these makes about a factor of 2 difference to the final figure. Instead of your 1 in 5,592,405 (chance of fit for any mapping) I get 1 in 2,676,939. That's for one particular scenario that's consistent with your data (I don't know e.g. how many boards both hearts and diamonds are impossible, so I just made something up), but the difference between choices should be minor in comparison, and I tried to make my choices fairly typical.

It seems a pointless thing to assume when you can just count how many times you hated each suit. Remember, we want to know how unlikely the board placement is to match this set of boards. We don't care how unlikely these particular boards are in the first place, since that's got nothing to do with the players involved, and we should therefore make sure our final answer isn't contaminated by having happened to pick a weird set of boards.

That's an extreme example, of course. But if one position happens to be quite a bit more common than the rest then an observer will tend to assume that corresponds to whichever suit is bad on fewest boards, and the simplistic calculation can significantly underestimate the probability of getting such a good fit by chance.

Paul's approach is potentially very robust. However, to get those neat powers of two I suspect he is assuming that all four board positions are equally likely. If they're not that could massively affect the answer (for example, if you never vary your board position and happen to come up against a set of boards on which you never hate a club lead, you'll always get a perfect match). The right (but significantly harder) question to answer is "What probability of getting such a good fit by chance can we achieve if we're allowed to choose how likely each board position is so as to maximise that probability?" Oh, and don't forget that we have to do that for each player separately, since they may put the board down differently from each other.

That makes no sense. If you don't have an agreement, but believe you do, you're mistaken. If, as a result of this belief you give an explanation, or make a call, that you wouldn't have done had you realised you had no agreement, then that is a mistaken explanation/call. (Of course, I don't believe this applies to the original case, since I think there was an agreement there.)

It is completely normal for a pair to believe different things in situations where they do have an agreement but one of them has gotten it wrong. It does not necessarily mean they have no agreement.

I don't think I would ever rule that the correct explanation is "undiscussed, but ..." here. I see two possibilities, and we need to ask a couple more questions to determine which is the case. They agreed to play "Capp in direct seat", but North misunderstood what "direct seat" meant. They agreed to play Capp by an unpassed hand sitting over the 1NT opener, and North wrote "Capp in direct seat" on the CC thinking it meant the same thing. In 2 there is a clear agreement that this is natural, and both the explanation and the CC gave MI. In 1 there is a clear agreement that this is two-suited, and the fact that North (unbeknownst to South) misunderstood their agreements does not change this fact. The CC is an accurate description of their agreement.

I did start my post with "I see a couple of problems with using this to resolve mismatches". My post was not intended as a comment on the merits of using S-B to score the tournament in the first place. FWIW I think it is a very good idea to compensate for the overall strength of your opponents, but this is a poor way to do it.

I see a couple of problems with using this to resolve mismatches (and suspect there are more I haven't seen yet). Since it works on the final score of opponents, it doesn't distinguish how much of the difference in opponents' scores was because of an actual mismatch, and how much is because of differences in their performance in subsequent rounds. And since you multiply the two together it works much better at reducing the score of a team that wins heavily when they are playing lower-ranked opposition than at increasing the score of a team that loses heavily against higher-ranked opposition (and the latter may be not at fault for the mismatch). In this case the first isn't so much of a problem as the mismatch occurred so late, but here you have the opposite problem that team 7 is punished heavily by this formula for facing weaker opposition in round 2 -- which was before the mismatch occurred!

Nor do we need to determine anything about the number of tricks that would be made on the ♣J lead, then, since the TD has done that for us too.

No law says that precisely (or even uses the word "peer"). There is a law which talks about "the class of players in question and using the methods of the partnership", but it is a law about UI and irrelevant to this case. A relevant law is 12B1: "[...] Damage exists when, because of an infraction, an innocent side obtains a table result less favourable than would have been the expectation had the infraction not occurred – but see C1(b)." To determine whether there was damage, we need to determine what would have been the expectation had the infraction not occurred, and whether NOS side got a worse score "because of the infraction". So we need to determine as best we can what this particular South (who decided to lead a diamond with MI) would have led without MI.

Then you're doing it wrong. How does polling a bunch of players who would never lead a diamond with either explanation tell you anything useful?

Peers in this context are people who might lead a diamond if told 4♣ was natural, so the lead is still relevant.

But the actual lead is relevant in determining what would have been led with correct information. And I see no good reason to believe the lead would have been different in this case, since the correct information doesn't make a club lead any more attractive (or a diamond lead any less attractive). If the situation had been different, with South leading a club with MI and a different lead working better, I would be happy to adjust on the basis that South wouldn't lead a club with correct information.

Law 57A3. I agree with the Chief TD FWIW. [edit: I find it curious that 57A says "declarer selects one of the following three options" (not "may select"), and so there appears to be no option to let West play whatever he likes.]

In the first room, I don't see why a club lead becomes more attractive with correct information. In fact I would much rather lead a club if told "natural", since then there is a good chance that partner will be able to ruff a club, either initially or when I get in with the ace of trumps and lead another club. In the second room I would have designated otherwise (not a penalty card), since West was partly responsible for it being exposed. Having allowed it to be a penalty card, it seems the TD should now adjust the score under 50E3, since NOS OS appears to have gained from the information. It is not clear how many tricks would have been made without the penalty card, so the adjustment should probably be a weighted score.

The harm is that when Stayman was alertable people didn't bother to ask about an alerted 2♣, because it was virtually always Stayman. This caused a problem on the rare occasions it was actually Keri.

Eh? There is no one board such that the result of the match without that board is known to anyone.

I agree with Zel and gnasher that requiring the match to be restarted with the previously played stanzas counting but no requirement to field the same lineups would, if legal, be preferable to either (b) or (c) above. Presumably, since the L&EC didn't give that as an option, the conditions of contest do not currently allow it, but in that case it would IMO be a good idea to change them for next year.

I know there was an attempt to shorten the Orange Book, and certainly in the past I have assumed that where an example was removed, that did not necessarily mean that it no longer applied (though in at least one case -- IIRC something to do with Walsh -- I have been told by Frances that I was wrong, and the reason it was removed was to change what was alertable). However, where an example has not been removed, but has been modified in a way that doesn't save any space (look at the BB -- it would easily fit onto one line either way), I can only conclude that the regulation has been changed in an attempt to, well, change the regulation.

Without any context, this would make sense. But the context is that the regulation has recently been changed from "after the next hand bids or passes..." to "after the next hand passes...", so someone must have thought about it and decided those two words shouldn't be there.

Yes, that's true, and yes, it's changed. 1♣ (1♠) 3♣ weak used to be non-alertable, then changed to being alertable with the 2006 Orange Book, then back to non-alertable when the Blue Book came in (2013 I think). The other two haven't changed in at least 20 years.

But the RA may "allow conditionally" the Watson double (which is a special partnership understanding, 40B2a). So allowing it on condition that you haven't psyched seems legitimate.