[cargobeep]

So your partner has opened the hand, and you have determined that you have about 26 HCP and a 4-4 major fit. Playing IMPS how do you decide whether to play 3NT or 4 of the major?

[wank]

 cargobeep, on 2012-October-31, 17:00, said:

So your partner has opened the hand, and you have determined that you have about 26 HCP and a 4-4 major fit. Playing IMPS how do you decide whether to play 3NT or 4 of the major?

unless you're at the highest levels of the game, just play the major all the time.

choosing to eschew the major fit requires a lot of very subtle judgements that would experts often get wrong too.

[Cyberyeti]

 wank, on 2012-October-31, 17:09, said:

unless you're at the highest levels of the game, just play the major all the time.

choosing to eschew the major fit requires a lot of very subtle judgements that would experts often get wrong too.

Agreed, if you think you have mirrored 4333s is the first occasion to maybe play 3N, but even then it can be wrong.

[rhm]

 wank, on 2012-October-31, 17:09, said:

unless you're at the highest levels of the game, just play the major all the time.

choosing to eschew the major fit requires a lot of very subtle judgements that would experts often get wrong too.

If you never start trying to develop expert judgement, you will never get it.

While the majority of 4-4 major suit fits should be made trump the scenarios where 3NT is better are not that rare
It is an interesting subject and there are clear criteria often written about in the literature.

Rule of thumbs are okay , but no substitute for thinking

Rainer Herrmann

[billw55]

Things that might suggest playing in NT instead of 4♥/4♠ include: weak trumps, values distributed across all suits, good intermediates, "slow" tricks, and balanced shape (especially 4333 which won't get any ruffs).

Usually such a decision is more likely to reap rewards at matchpoints though.

[helene_t]

If partner knows that you have a 4-4 fit then you can bid suggest 3NT, partner will pass with a 4333 shape and maybe with some 4432 shapes with something like Qx in your suit.

This is exceptional, though. An auction like
1♦-1♠
2♠-3NT
is not a suggestion to play 3NT despite the 4-4 fit. It is a suggestion to play 3NT in case opener has 3-card support. With 4-card support he should almost always correct to 4♠.

[zasanya]

1♣-1♥-2♥-3NT if responder is 4-3-3-3. Opener will convert if he has ruffing value.
1♣-1♠-2♠-3NT as above
1♦-1M-2M-as above
1NT-with 4-3-3-3 responder bids 3nt.
Cant think of other auctions which meet conditions given in OP.

[mikestar13]

 billw55, on 2012-November-01, 06:38, said:

Things that might suggest playing in NT instead of 4♥/4♠ include: weak trumps, values distributed across all suits, good intermediates, "slow" tricks, and balanced shape (especially 4333 which won't get any ruffs).

Usually such a decision is more likely to reap rewards at matchpoints though.

Your decision criteria are right on the money, but your preference for making the decision to bid 3NT more often at matchpoints is misguided. Rejecting the 8 card fit is more likely correct at IMPs (see Kit Woolsey's excellent book Matchpoints, which goes into a great deal of detail about this decision in both forms of the game.) The upshot is that the cost of being wrong is higher at matchpoints in the common case where 3NT and 4M both make and the major takes one more trick. Being +600 when the field is +620 is a disaster at matchpoints, but only costs a lousy 1 IMP in that game.

[P_Marlowe]

We play the major.

If you go this way, you can use a 3NT bid, after a major suit fit got located as a
slam probe.

This is a proctical decision, and you will loose out sometimes, the usage of the 3NT
bid will give you some compensation, and it simplifies life.

I would not worry to much, about this issue, and focus on other more important issues.

With kind regards
Marlowe

[rhm]

 mikestar13, on 2012-November-01, 20:28, said:

Your decision criteria are right on the money, but your preference for making the decision to bid 3NT more often at matchpoints is misguided. Rejecting the 8 card fit is more likely correct at IMPs (see Kit Woolsey's excellent book Matchpoints, which goes into a great deal of detail about this decision in both forms of the game.) The upshot is that the cost of being wrong is higher at matchpoints in the common case where 3NT and 4M both make and the major takes one more trick. Being +600 when the field is +620 is a disaster at matchpoints, but only costs a lousy 1 IMP in that game.

Not sure whether I buy this.

You might just as well argue:
The upshot is that the cost of being right is higher at matchpoints in the common case where 3NT and 4M both make and the major takes no more tricks. Being +630 when the field is +620 is a triumph at matchpoints, but not even worth a lousy 1 IMP in that game.

It all comes down of being right.
At Imps you look for the safest game, at matchpoints the hunt is for tricks
I of course are aware that you argue, that a single ruff in either hand may bump up your trick potential.

As Morehead commented already more than 50 years ago, when espousing the merits of 4-4 fits in his excellent book "Morehead on Bidding"
"A 4-1 or 5-0 break occurs one third of the time. Few of the examples shown would have played better then."

Another aspect often overlooked is that you far more often get a favorable lead in 3NT, which allows you to take one trick more than you are entitled double dummy. This also happens at trump contracts but less frequently.

Rainer Herrmann

[billw55]

 rhm, on 2012-November-02, 03:49, said:

You might just as well argue:
The upshot is that the cost of being right is higher at matchpoints in the common case where 3NT and 4M both make and the major takes no more tricks. Being +630 when the field is +620 is a triumph at matchpoints, but not even worth a lousy 1 IMP in that game.

It all comes down of being right.
At Imps you look for the safest game, at matchpoints the hunt is for tricks

Agree, either the major takes more tricks or it doesn't, and either result will strongly swing a matchpoint score. It's really hard to tell which is going to happen.

[Antig2]

I prefer to play 4♥♠ when the points are from high cards. If I hold many queens and jacks may consider 3nt especially with unfavorable shape. In such case it doesn't hurt to bid 3nt and wait for partner's bid. When I bid 3nt I would like to have 10's too. They rarely have value in 4♥/♠.

[campboy]

I suspect that the Woolsey argument above holds for hands with marginal game values: if it is right to be in 3NT at MP because both games might take the same number of tricks then it is likely right to be in 3NT at IMPs because that number might be 9. However one of the main indicators for preferring 3NT at matchpoints is having significant extras, and those hands are likely to be better in 4M at IMPs for the reasons rhm suggests.