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All comments by Christopher Monsour
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I'm calling bullshit on this. The probability of 1 being short increases by at least about a quarter if you are playing strong NT vs weak NT, and by between 4.5 and 9 percentage points (depending on your choice-of-suit philosophy with 4+ diamonds or a 5-card major in a balanced hand). If that isn't a big effect, then Mt. Everest is just a mole hill.

12-14 point hands are approximately 20.6% of all hands. 15-17 point hands are approximately 10.1% of all hands. 18-19 point hands are another 2.6%. (See http://web4dmarch.com/bridge/stats/hcpstats.pdf) These percentages will change a little but not change too much is we restrict to balanced hands.

So you open 1 or 1 on balanced hands (the only source of two-card and three-card club openings) approximately (20.6+2.6)/(10.1+2.6) = 23.2/12.7 = 1.83 times as often when playing strong NT as when playing weak NT.

Of course, you will also open 1 less frequently overall when playing a weak NT, so let's correct for that, using that 4432 are 21.6% of all hands, 4333 are 10.5%, and 5332 are 15.5%, adding to 47.6%

Let us say that you open approximately 25% of unbalanced 12-19 point hands with 1. (Pretty close to true if you open 1 on 4414 and 4144 shapes but never on 55 shapes.) So, out of 100 hands in the 12-19 range, 100*.25*.524 = 13.1 are unbalanced and open 1. If you play strong NT, 23.2/(23.2+10.6)*.476*100 = 33.2 are balanced and open a suit. If you play weak NT, 12.7/(12.7+20.6)*.476*100 = 18.2 are balanced and open a suit.

Approximately 63.7% of balanced hands have only 2 or 3 clubs. Thus, if you always open balanced hands outside of your NT range with 1, the chances that your 1 opening is on 2 or 3 card is 0.637*33.2/(33.2+13.1) = 45.7% if you play strong NT and 0.637*18.2/(18.2+13.1) = 37.0% if you play weak NT.

Thus, if you always open balanced hands outside of your NT range with 1, the probability that a 1 opening is short increases by almost 9 full points depending on your NT range.

If you follow a traditional approach of opening balanced hands 1 only if they have at least three clubs, no five-card major, and not four diamonds, then you open 47.4% of balanced hands 1 that are opened with a suit, and 31.2% of those (14.8% of the total) will have three clubs only. Thus, if you play strong NT, your 1 will be short 0.148*33.2/(.474*33.2+13.1) = 17.0%, but playing weak NT it will be short only .148*18.2/(.474*18.2+13.1) = 12.4% of the time.

Most bridge players are too innumerate to be trusted to understand what adjustments will be significant. A simulator isn't a substitute for thought. Rather, a simulator is to most bridge players what a sharp knife is to a 3-year-old.
July 22
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The same thing applies to making a 2/1 response to a major holding four diamonds and three clubs. Responding 2 can make it easier to find a diamond fit.
July 21
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The weaker the NT range, the fewer short openings there will be, since more of the balanced hands get opened 1NT, since weaker opening hands are more common than stronger ones. Also, opening offshape NTs with long minors will reduce the number of hand with 5 or 6 card suits that are opened 1.
July 21
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“Strong notrump” can also mean 14-16, or 16-18. And it also matters what you would open with 5m422 and with 5M332 in your NT range. Not to mention 6m322.
July 21
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Amazing how people think they can answer this question to 4 significant digits without knowing your notrump range! LOL
July 21
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Richard, I don't know that increasing the expected chance of comparing one or two boards with any given opponent from 48% to 80% represents a huge decrease in security, since few people would go to the trouble of sifting through 96 boards just for that, especially since the other person might be planning to turn them in.

However, if that is too much of a decrease in security, I think flight A would be better off with flight A comparisons only in a way that wouldn't decrease security. If half the total entries are A, I'd much rather base the score in A on 9 A comparisons than on 18 comparisons almost half of which are against inferior players.
July 19
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If you play the 10 at trick one, declarer wins the J and can come to three clubs and (if you attack hearts) two tricks in each of the other suits, giving up the lead only twice…once in each minor. If he needed the third spade, he'd still need to knock out your K, and the 10 play wouldn't actually have cost a tempo.

If you never attack hearts he'll need the third spade trick, but if you never attack hearts he'll also have time to set it up.
July 19
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I rarely mean to be contrarian. But that was an outright joke–Perhaps I should have used a smiley. And I don't think a high spade lead is ridiculous at all. I would have led the 2 against this auction, but I'd probably lead 8 against 1NT(15-17)-2-2-3NT.

It is difficult to defend this deal third hand. Putting in the 10 isn't good enough but only because declarer is so chock full of 8s, 9s, and 10s…he has J9x K98 K109 A109x, yes? On some deals the advantage of inserting the 10 is that you get in later when you have a much better idea what to shift to next. On this deal, that doesn't work since declarer doesn't need the third spade trick.
July 18
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How can I make a joke and not be mistaken for being serious?
July 18
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Maybe if your partner is a devoted Bird/Anthias fan, he should lead suit preference from xxx.
July 18
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Bob, the winner would be the player who won the top flight. Anyone could enter the top flight, but players with fewer than, say, 5000 masterpoints could enter a different flight if they wished (for those who need a refresher on the meaning of “flight”).

Richard, the top flight might consist of 1000 players out of a total of 3000. At 18 comparisons per board out of a field of 1000, I don't see how that "defeat[s] the whole security model". It hardly impacts it at all.
July 18
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I see how this works. In North America we assume EBL masterpoints must be more valuable than ACBL ones, and in Europe you assume the opposite. ;)
July 17
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I also think 4 should ask whether the 3NT bid was based on power or a suit. But I think 4 should say it was based on some suit (if you need to work out which one and can't do so, you probably shouldn't have bid 4) and 4 and higher should say it was based on high-cards but give ranges. I used to play 4NT = 15-17, 4 = 18-19, 4 = 20+ with a 4 re-ask. These days I'd probably invert that and make 4 the weakest so that responder can sign off in 4 or 4 opposite a minimum strong NT.
July 17
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Assuming 2 promised at least invitational values, it's important to be able to do three things:
(1) Show whether your hand is a maximum or not;
(2) Show or deny possession of four hearts;
(3) Penalize them if they stepped out of line.

I think this last one is important. You presumptively have a playable trump suit in clubs. You also have the balance of strength. And responder knows opener's range pretty well. You should be able to wield the axe just as you would if the auction has started 1-(P)-2-(2).

Also, it's not like no one has ever psyched once they know your side has the balance of strength. If 2 was opened in second seat, for example, some joker might toss in a lead-directing 2 call on a void (having passed initially, hoping that might help his partner work out what is going on).

Finally, one thing NOT to try is to defend 2 undoubled. The 2 response presumably committed you to play at least 3. Now that you've been deprived of bidding space, don't waste more space by giving up a more useful meaning of “pass”.

Here's what I have been happiest with:
Pass = Maximum, one-suited in clubs, forcing. Not void in spades and not often a singleton. (This doesn't just help partner with the axe. It helps with choice of games when he has, e.g., Axx in spades.)
Dbl = Penalty
2NT = non-maximum with four hearts (forcing one round, so you needn't be minimum, but responder will often try to sign off in 3 assuming that you are)
3 = any minimum without four hearts not suitable for a double
3, 3 = max values, at least four cards in the suit, forcing to 3NT or 4 of a suit
3 = 0-1 spades, max, completely GF, usually seven clubs but could be a very strong six-card suit.
3NT = solid suit and fast spade stopper. You take this route to 3NT rather than the slower one of passing first (and giving partner a chance to play 3NT from the right side) because you fear LHO is about to raise which may allow RHO to find a profitable sacrifice against 3NT. Not a bid you are likely to make at favorable vul, for example; in that case, pass, and don't preempt partner.
July 17
Christopher Monsour edited this comment July 17
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I think stratifying this event is a terrible idea. I think it would be much better to flight it. Given that the ACBL seems committed to a miniscule number of comparisons per board, it's important for the top-level competitors that those comparisons be against other top-level competitors. After all, the usual reason to stratify rather than flight is that flighting would make the field too small. That isn't an issue here at all. The usual reason to flight is to improve the quality of the comparisons, which is a huge issue here.

Although I wouldn't make it a priority, the ACBL could also experiment with the flight B format I've always thought they should try for events like the 1.5K LM pairs: Instant matchpoints based on the results in the open field….
July 17
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Although I think that, in the spirit of the 21st century, David was trying to replace it with “rectidigital”.
July 16
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It is very odd to refer to it as the “Toronto” robot event, don't you think? ;)
July 16
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Suppose the 3 bidder had been dealer, so the auction was the same but without the 1 opening. Now North's 4 raise is reasonable (I'd do it myself), but there's a big difference because he can hope to buy a lot more from South. On the actual auction, North reopened with a double after South showed no force opposite a strong club. Since North has promised more here, South will be much more aggressive about bidding 4 himself. For example, KJ10xx xxx x xxxx would be an absolutely clear 4 bid over the double for South on the strong club auction, so North can't hope to buy even that much.
July 16
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Do you really think North's 4 doesn't warrant a stronger adjective than “questionable”? Or are you just being diplomatic?
July 15
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I agree, John. It's sad, though, that it even requires comment. One would have thought common sense would suffice. And I wonder what you can do about the kind of people who tell everyone else, before the events air, the results of sporting events that air with a tape delay (USA-USSR 1980 comes to mind). Maybe one purpose of the practice events could be to find out such people and ban them from the July 23-26 event?
July 15
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