rogerclee

I think someone who leads a diamond and thinks it's automatic has a basic flaw in his understanding of how tricks are taken at bridge.

To me 4S is something like a hand with a lot of spades and constructive values but is not very strong (ie no forcing pass if they bid 5H), I would always think this undiscussed playing with another expert, but I'm not aware of any standard definition. Thinking about it a little, there is some logic to playing it shows a spade slam try with no heart control, since that is an impossible problem playing standard methods without forcing to the 5 level. (There are many other "impossible" handtypes you could make it show on this auction). Sorry to sidetrack the thread a little, but you are thinking about this auction the wrong way if you think it's primarily about strength, shape is more important. On this auction, when you have a decent hand, correct strain is the most important thing to sort out. Here are some questions you want the answers to: 1) Should you play spades? Differentiating between 4 vs 5+ is very important. 2) Should you play NT? 3) Should you play opener's minor? The other minor? 4) Should you just defend 3HX? Obviously you cannot answer all these questions very accurately anymore, that's why they bid 3H. In response to TylerE, if you think about these questions correctly, you will quickly deduce that playing 3S nonforcing is very bad. It caters to an unlikely and less important handtype (competitive but less than invitational with spades) while making it very hard to answer questions (1) and (2), since strong hands with 5 spades are at a total guess as to what strain to play, since playing a 5-3 spade fit will usually be right, and playing a 5-2 spade fit will often be wrong. It seems like TylerE is using X to show all decent hands with 4-5 spades, and just guessing to bid 4S (or 4H) with 6+ spades. The degree of your spade fit is the most important thing to sort out on this auction. Double, necessarily, must cater to the most handtypes, since it is the most flexible action. It is not uncommon to X on a hand with 3 spades and no convenient bid to make. Diluting your most flexible bid to show 3, 4, or 5 spades is a bad way to play bridge, it makes determining whether you should be in spades very difficult, while not gaining a lot in having a NF 3S bid. It also makes determining when to pass out 3HX very difficult, how can you defend 3HX with a random stopperless 3334 when you could easily have a 5-3 spade fit? Again, sorry to sidetrack, but I see a lot of intermediate/advanced players such as TylerE thinking about these kinds of auctions the wrong way. Strain always takes priority before strength, this principle applies in many auctions where you don't have enough bids to show all the handtypes you would like to show.

This is not an argument for blasting game when you have the option of inviting, this is a pretty basic fallacy. What you should really be simulating is how often game makes opposite a hand that would not accept an invite, not any hand period.

There are certainly hands where I would bid 3C on a doubleton but this is definitely not one of them.

FTFY

BTW I did not mean to imply that 4SX usually makes or anything, by far the most likely result seems to be down 1 when it goes all pass, which is actually pretty solid equity for doubling, since all those win 2's add up.

Yeah, I tried to be neutral and just look at them and be honest. I've looked at about 30 hands so far, sorry I didn't calculate actual IMP gains/losses. My friend Eugene Hung did some analysis into the problem and I will look at his hands later. Things I learned: 1) It's wrong to pass, not that close. 2) 4SX is not a great auction for your side, for a not-so unexpected but unintuitive reason. Partner is usually just balanced, and given how weak our diamonds are, and how his diamonds are not good enough to bid, they have a double spade+diamond fit, or dummy's diamond values are all working. 3) Partner bids 5D surprisingly infrequently, way less than I thought, he usually either passes or has a 4N bid available. Seeing partner bid 4N is a huge winner for your side, usually they sell out to 5C/5H but nobody can really double, or they take the push. When partner bids diamonds it's pretty bad but not necessarily so, I saw 2 hands where it's pretty normal for them to take the push, saving you from the 5-2 fit when the 4S bidder is the one with diamond length. 4) 5C, which I thought was a really bad bid, is a serious contender, but it's going to take more analysis to decide if it's better than X, which I guess I can look at in more detail tomorrow. I spent most of my time analyzing pass vs X, when it's now obvious I should have been looking at X vs 5C. Anyway, overall a learning experience for me.

I did a quick sim and just looked at hands where I thought opening 4M was at least reasonable without DD analysis or anything. Preliminary results say 5C shouldn't be discounted so easily, it's not doing too bad so far. Double seems to have tremendous upside and downside (on one hand partner has a clear 5D bid and diamonds are 6-0 with KQ9xxx behind), will need to look at more hands, but currently it looks better than pass.

pass

Well, in fairness if our hand was the same missing the ST we would make anyway on a neutral return, which complicates the problem a bit in theory. In practice it would be difficult for a defender to figure this out easily at the table.

I agree with the statement, but I don't really have any serious doubts about this one, easy pass.

Nice play from AQxx and a stiff heart, but Axxx is just more likely -- in theory, and certainly in practice. Edit: Just to clarify, I didn't mean that Axxx is more likely than AQxx, it isn't, but Axxx and 2 or 3 hearts is certainly more likely than AQxx and 1 or 4 hearts, even though AQxx gives more freedom to the arrangement of the other HCP.

You might be shortchanging the accomplishments of a lot of the posters. Frances, gnasher, jallerton are all considered top English players, philking was a coach for the open English team before I think, MFA is a top danish player, JLOGIC is one of the best players in the world period, etc.

north is pretty bad at bridge

I would pass with some reservations, tough problem. I think I prefer 4N to 4S, 4S seems like taking an IMO antipercentage gamble regarding the quality of partner's spades.

I thought this was the most interesting of all the threads you started Frances, I hope you will post the results and your thoughts on this problem.

On hand 1 I feel a spade is normal, we have 4 reasonable spades and no extremely attractive alternative. On 2 I lead a boring low club.

I'm on board with the S7 followed by re-evaluating what to do after a few tricks. I have had bad experiences trying to beat them after seeing the HQ float around to the king, it just seems like they always have 9 after that when I have no outside fast entry. HA has some appeal, I like to make leads where there is a clear and simple layout where it works well, and on this hand that is declarer with singleton K. I think I prefer it to the HQ.

First one west, keycard is a great convention. Not crazy at all for him to guess to bid 7D over 6D either, given how bad his previous bid is. East could have done more but I am not particularly used to my partners not just bidding keycard with two aces opposite a huge hand and a fit, so he probably just thought his partner was only interested in 5 vs 6. Second one, I think 4D shows a minimum, and I would not call the east hand that. Despite the club "waste" he knows that they are in a big fit (4C is almost always 5+D) and he has a stiff, so I would have cuebid 4H. West bids keycard and finds out his partner has two aces and the king of clubs but I don't think that's enough to bid 7, so I wouldn't get there. BTW you don't need diamonds 2-1, there are 13 tricks even after 3 rounds of trumps as long as there is no club ruff.

If it's undiscussed then it's takeout.

Spade, just seems like the lead that needs the least to be right.

I learned to try to lead as passively as possible against this kind of auction, so I would lead a diamond.

I tried to make it clear that I thought that doubling on hands like the one is a partnership decision, not one that I would just do. I also said it was close, and that either style of bridge is fine to me. TBH I would not be surprised to learn that a lot of good players disagree with something I wrote. That seems fine to me, it was not geared towards top players. The thing I wanted to underscore the most is that non-experts tend to be too passive in the auction. I wanted to show a lot of hands where a non-expert would probably consider it insane to bid, when in reality it is reasonably close.

There's gonna be a few more, stay tuned!