[awm]

Are there any studies which quantify the advantage of playing 3nt from the stronger side?

I'm particularly interested in two balanced hands without a major fit, maybe 8-11 opposite 17-19.

[benlessard]

IMO its not just the strenght as the failure to overcall.
1D--(P)--3NT

4Th seat is more likely to have an easy lead than 2nd seat.


When its a 1Nt/2NT that show no majors you often rightside if declarer got only 2 cards and dummy 3 or 4 in the suit lead.



Where few people make the effort and I believe there is a fair amount of imps to be won is when there is 3 suit bid below 2NT. A system that allow you to grab NT with Hx (Kx,Qx,Jx,Tx) & make partner declarer with Axx/Kxxx is a clear winner.

[wodahs]

I was curious myself, so did a quick and dirty double-dummy sim. For what it is worth:

North has 16 balanced, South 9 balanced. Contract is 3NT.

North makes 60.7% of the time, making average tricks of 8.76.

South makes 58.6%, with 8.69 trick average.

That's about a 3-4% edge (to making the contract), as defended and played by Deep Finesse.

[Kaitlyn S]

wodahs, on 2017-June-17, 18:34, said:

I was curious myself, so did a quick and dirty double-dummy sim. For what it is worth:

North has 16 balanced, South 9 balanced. Contract is 3NT.

North makes 60.7% of the time, making average tricks of 8.76.

South makes 58.6%, with 8.69 trick average.

That's about a 3-4% edge (to making the contract), as defended and played by Deep Finesse.

In reality, the advantage is probably more; Deep Finesse defends double dummy, and IRL it's a lot easier to defend with 16 of declarer's 25 points on the table rather than 9. And while a dummy dummy lead is unlikely to give anything up, a blind opening lead up to a 16 point hand is more likely to give up a trick than a blind lead up to a 9 point hand. (I'm ignoring bidding considerations; assume it goes 1NT-3NT to have the 16 point hand play and 1C*-1NT-3NT to have the 9 point hand declare. (1C 16+, artificial).

[awm]

Kaitlyn S, on 2017-June-17, 20:47, said:

In reality, the advantage is probably more; Deep Finesse defends double dummy, and IRL it's a lot easier to defend with 16 of declarer's 25 points on the table rather than 9. And while a dummy dummy lead is unlikely to give anything up, a blind opening lead up to a 16 point hand is more likely to give up a trick than a blind lead up to a 9 point hand. (I'm ignoring bidding considerations; assume it goes 1NT-3NT to have the 16 point hand play and 1C*-1NT-3NT to have the 9 point hand declare. (1C 16+, artificial).

This isn't totally clear -- there are also holdings like Axx opposite Qx or Kxx opposite Jxx where it tens to be advantageous for the opening lead to go into the weaker hand (barring a lead like Q from AQTx on the second hand that most people won't find at the table). Might be interesting to run the double-dummy sim again assuming the lead is "fourth from longest and strongest" (not that people should or will always lead that way, but to give at least an estimate).

[Fluffy]

You are probably better using real data than simulations on this one. But I agree with Kaitlyn, double dummy will tell defenders not to lead from KQ10xx or KJ10xx when everyone on the planet would.

[rmnka447]

Also agree with Kaitlyn S.

When the stronger hand is concealed, there's a whole lot more the defense has to figure out about it to find the best defense. More often than not, the stronger hand is the master hand that is trying to be set up. So having it exposed likely helps make the defense clearer.