campboy

I think the fact that RHO accepted 3♠ is authorised, but that information alone doesn't necessarily help. We can't tell from AI whether RHO accepted the IB to stop partner substituting 4♠ or to stop him substituting a pass -- only the UI from partner's withdrawn call tells us which. (I agree with Lamford, though, that pass isn't an LA whatever.)

My point was simply that it is wrong to penalise North for his one law 9 infraction while ignoring West's two. Which was what lamford seemed to be suggesting we do.

That would be true, were it not for the introduction to the laws, which specifies how "should" is used. But that is not really my point. Of course I interpret the law as you say when actually ruling. But IMO it is ridiculous to use the passive voice at all; if this is to be an infraction, the law should specify who committed it.

Ah, yes, I misread your question.

No: 19A1.

We're on firmer ground with a call out of rotation: it's an irregularity because of Law 17C.

They may have all breached 9B1, but West is the only one who also breached 9B2. Um. I was going to say that West had broken three laws -- 9B1, 9B2 and whichever law says it is illegal to make insufficient bids. But I can't actually find one -- anyone know what it is?

I don't really see how one can say "that's not legal" in a way that suggests no penalty is going to be claimed if it is corrected. Putting "dummy" down when you are declarer is a different matter, of course, since that is an irregularity in itself, and it is completely illegal to do it deliberately. Personally, I would welcome a change in the law to say "When attention has been drawn to an irregularity, the player who drew attention should immediately summon the Director. If he does not do so, any other player (including dummy) may summon the Director." But we do not have such a law at the moment. The current Law 9B1a is completely ridiculous. A literal reading of it (taking into account the introduction to the laws) is that failure to be summoned immediately is an infraction committed by the Director. Average-plus to both sides, then?

You might think he should say that, but what North said is not illegal. The laws expressly permit him to draw attention to the irregularity. I don't see why you think North has done anything wrong -- it was West who breached 9B2 by taking an action (bidding 4♠) before the director arrived.

I disagree. North has a right to draw attention to the irregularity (Law 9A1). Once he has done so (but only then) the TD should be summoned at once (Law 9B1a). But any player may do this (Law 9A1b) and North is no more responsible for doing so than anyone else is.

The point is that there was a pause between the 3♠ card being put on the table and someone pointing out that it was insufficient. If, during that time, West saw that the card said "3♠", there was a pause for thought -- had she really intended something different, she could have corrected it at that point, whether or not she also realised that 3♠ was insufficient. Of course it is possible that West didn't see the bidding card until someone else said it was insufficient. But if that's the case, I would be asking why she didn't see it. Players normally do look at the bidding cards as they make bids.

This is covered in the Blue Book: So the case OP was asking about is always fine, but changing between natural and strong club, say, would not be allowed in short-round events.

Of course it can suggest a left turn over a right turn, depending on the probabilities involved. If there is a BIT which is very likely to indicate the sort of hand that would make a left turn more attractive, the fact that occasionally it will turn out to be based on a completely different sort of hand does not stop the left turn being suggested. Here I think bidding on is suggested over pass. Whatever partner was thinking of doing, I would be happier if he had done it. Because of the BIT, it looks like we are heading for a bad score defending 4♠ undoubled, whereas I think there is a decent chance that we will get a good score if I bid. Without the BIT I would be happy to pass.

If you adjusted because a player's pass, following a slow pass from his partner, was judged unacceptable, I fail to see how the table score can possibly have been 5M making by OS.

Well, it doesn't satisfy 73F unless East "could have known" -- if the change of line was truly irrational, how could he have foreseen it?

A misbid is not done on purpose either; in a misbidder's mind the bid is systemic. Of course he is wrong, so opponents are not entitled to know about that bit of "system".

I think an IB is more like a misbid case than an MI case, because it is the player who made the bid who is under a false impression, not their partner. And like a misbid, opponents aren't entitled to know what that false impression is.

Of course the IB had a meaning -- to the player making it. It normally doesn't have a meaning to their partner, who isn't aware of what was going through offender's mind at the time. Say it goes 1NT (3♠) 3♥, like in Vampyr's example. Now the possible meaning to offender could be one of (at least) three things. like 1NT - 3♥, because he hadn't seen the overcall. like 1NT (2♠) 3♥, because he misread the overcall. like 1NT (3♥) 3♠, because he just got a bit confused. Now I think NOS should be entitled to know what those possible meanings are (that's partnership understanding). What they should not be entitled to know is which one it is in this particular instance (although of course if offender used the stop card they would be able to guess).

Yes, because 1♥ and 2♥ are both non-artificial (27B1a). The TD might subsequently adjust under 27D.

The Blue Book was printed (and sold at Brighton) in 2013. There was no 2014 printing, but I was told this was only because the changes to the text were sufficiently minor it was not thought worthwhile. Certainly my impression was that future print runs could be anticipated.

The only law that gives players a right to know what future bids mean is this one. The RA has specified that this should be done by exchanging completed convention cards. To give opponents the gist of your system verbally, and spare them the trouble of reading it, is simply a courtesy. What is true is that there is nothing in the laws that gives players the right to ask specific questions about future bids. All you get is what is (or rather should be) on the CC. Anyway, all the opponents are entitled to is the partnership understandings. Most partnerships have no understandings about insufficient bids beyond "we try not to make them".

It's still silly. The 3 IMPs that is defined in the laws is "in IMP play". That applies just as much to cross-imps as to teams of four. So if you are taking 3 IMPs as an absolute value handed down by law, then average-plus for cross-imps should be 3.00 IMPs. The EBU decided to use their powers (given in Law 86A) to vary the value of average-plus in IMP play. Earlier editions of the WB gave a formula to be used for various numbers of tables. IIRC the figure for teams of four did in fact work out at 3 IMPs, but only after rounding.

At the risk of derailing the thread by answering the original question... The justification for the 70% rule (which, like the pirate code, is really more of a guideline) is as follows. First, the EBU VP scales are (or were – not sure if this is still true) designed so that in matches between equal-strength teams of average ability, each VP result will be approximately equally likely. To maintain that property when applying to other forms of scoring, the scaling factor we should use is the quotient of the standard deviations -- that is, the standard deviation of the total crossimp of one pair from n tables of equal-strength pairs, divided by the standard deviation of the IMP score between two equal strength teams. Different boards are independent if we assume the teams/pairs are indistinguishable, so we can do everything board-by-board and get the same scaling factor. Now, assume that on a given board these indistinguishable average pairs will produce scores independently with some distribution, with mean m and variance s2. It is easy to check that for a teams match the variance of the swing in total points is 2s2, and that the variance of the total of a pair's swings against all the other pairs is n(n–1)s2. So, assuming the IMP scale is linear, you should divide by the total number of scores (n) times sqrt((n–1)/2n). This last figure will be a little less than sqrt(0.5), and 70% is indeed a little less than sqrt(0.5). Now of course the IMP scale is not actually linear. But this means that the problem is no longer exactly soluble – the scaling factor will depend on the unknown distribution above, and will be different for every board. The overall average scaling factor will be something close to sqrt(0.5), will depend on n, will probably be less than sqrt(0.5) for smallish n and there is simply no way of getting enough information on the distribution of swings between average evenly-matched teams to give it any more precisely than that. So I for one do not object to the WB giving a figure of 70%. It is an approximation to an exact solution to an approximation of the problem. Since we can't do anything about the second "approximation" in that sentence, it is silly to nit-pick about the first. Likewise it does not bother me that average-plus is 2 IMPs rather than 2.12. The figure of 3 IMPs for teams of four is rounded to the nearest integer in the first place, and it is pointless to take something rounded to an integer, multiply it by sqrt(0.5), and then give 2 decimal places of the answer as if they mean something.

I suppose technically any call North makes before we get there falls under 28B's "before rectification has been assessed". This causes problems if it is, say, a double. It would make more sense to be able to ask North whether he intended to call over 1♠ or to make an opening call, and apply 29A or 28B respectively. It's a bit early for me, but hopefully someone can come up with an argument why this is consistent with the laws. There is nothing in the White Book about this.

You don't have to draw attention to the revoke at all, of course. If no-one does, there is no obligation to call the TD.