[mikestar13]

I think responder should gamble 4♥ instead of doubling. True opener may have only two, but ♠ is probably opener's short suit, as they almost certainly have a nine-card fit (certain if they play LOTT).

[DinDIP]

Free, on 2010-October-22, 02:07, said:

DinDIP said:

1. I'm with Rob. This auction is difficult whenever 1♦ just shows strength, whatever the range. Sure O has more options after a 1♦ pos but how do you find a 5-3 H fit with confidence?

2. These hands are easy with some semipos responses but not others. So, after a 1N response that shows 5+H, O has enough (with the promoted SQ) to bid 4♥. But what if the response were a majors-first principle 1♠ showing 4+H UNBAL? If 4th now bids 2S
1♣ (P) 1♠ (2♠)
would you bid 3♥ as O when you might have a 4-3 fit?

1. what you don't realize is that opps won't compete overagressively if you have a penalty Dbl available. So they will have a 9 card fit pretty much all of the time. This makes it easier in this case for responder to just bid 4♥ since he can expect partner to have 3+♥.

2. there's a reason why this semipositive structure was formed based on 5 card Majors. These responses are made to make competitive auctions easier, not to have something which is different for fun. If you first deny a 5 card M with your SP (1♥), then you can safely bid your 4 card M later on if necessary. It's with reason why Richard and I are really against a structure where you combine ALL semipositives into 1 response.

1. Maybe, but it's still the case that it's harder to find a fit if all you've done is to say something about your hand's strength and nothing about its shape. If O's pass is the equivalent of a takeout X and R bids 4♥ how does O know if R has 4 or 5 or 6H? There's still a lot of guesswork involved and this on hands where we know we have the values for game and often for slam.

2. I agree that showing 5+M semipos hands will often work well. But that comes with a price; on other hands O's decision about whether and how to compete will be affected by knowing whether R has 4 cards in a major. An ambiguous response like 1♥ that lumps all semipos without 5M doesn't provide O with that information. And Marston's structure means 2N and 3-level responses are not available to show other semipos hands with (say) length in the minors. That's less likely to be critical (because the suit is a minor and not a major) but there is still some cost. As always, different structures have plusses and minuses; and when the plusses come up the system looks great.

David

[Free]

DinDIP, on 2010-October-30, 01:58, said:

1. Maybe, but it's still the case that it's harder to find a fit if all you've done is to say something about your hand's strength and nothing about its shape. If O's pass is the equivalent of a takeout X and R bids 4♥ how does O know if R has 4 or 5 or 6H? There's still a lot of guesswork involved and this on hands where we know we have the values for game and often for slam.

2. I agree that showing 5+M semipos hands will often work well. But that comes with a price; on other hands O's decision about whether and how to compete will be affected by knowing whether R has 4 cards in a major. An ambiguous response like 1♥ that lumps all semipos without 5M doesn't provide O with that information. And Marston's structure means 2N and 3-level responses are not available to show other semipos hands with (say) length in the minors. That's less likely to be critical (because the suit is a minor and not a major) but there is still some cost. As always, different structures have plusses and minuses; and when the plusses come up the system looks great.

David

1. 1♣-1♦-(1♠)-1NT already denies 5♥, so when the auction continues ...-(3♠)-pa!-4♥ it's clearly a 4 card suit. If responder bids 4♥ instead of pass then it's 5+♥ and opener isn't supposed to run away with most doubletons. It's not always perfect, but it works well most of the time.

2. It's all about frequency. If semipositives are more frequent than GF, then you want the system to work well with semipositives and acceptable with GF. If it were the other way around (like with a 1♣ opening 17+ or 18+ I think) then obviously it's better to treat your GF hands as good as possible and don't bother about semipositives. So yes, the system looks great if a SP comes up (which is a lot), we manage with the GF hands which are less frequent, and the double negatives are the worst. The impression I get is that using SP like we suggest solves most of the problems everyone is having using a normal negative, and that the problems we encounter when we have a GF are much smaller compared to these. The double negative is worse (1NT rebid by opener has a huge range for example). Lucky it's pretty rare that we have a DN and opps stay quiet. I admit that it may (not sure however) be more useful to just bid 1♣-3m with SP, but the price is that you lose efficient relays. As always in the MOSCITO philosophy, part scores are less important than game and slam bidding. This is why Marston doesn't use 2NT and higher as SP, he prefers to keep slambidding as accurate as possible for all hands SP or stronger.