[NickRW]

TimG, on Oct 8 2008, 12:48 AM, said:

NickRW, on Oct 7 2008, 04:30 PM, said:

I don't think that sequence shows 15-17 bal or equivalent.  What is partner to bid with a 12hcp 1-4-5-3 shape, for example.  I admit partner is likely to have something extra in terms of stength or be unbal.

From the KS summary provided at the Bridge World site:

"Usually 15-17, 4-card fit. Could be unbalanced equivalent. Rarely, 3-card support, too concentrated for 1 NT rebid: ♠AQx ♥xx ♦xxx ♣AKQxx."

If the 1=4=5=3 12 HCP hand does not qualify as 15-17 in support of hearts, it is probably right not to open (in the context of KS).

Well, I can see where that's coming from, but I don't agree with the KS idea of hand evaluation in that case. This sort of thing is quite a reasonable opener to my mind (maybe not in KS - which is not my system) - anyhow:

x
AQxx
KJ9xx
QTx

But if you're saying that, in support of hearts, the above is equivalent to:

xx
AQxx
KJxx
AJx

Well, if that is the case, remind me not to play KS.

Nick

[TimG]

FWIW, some simple simulation results.

Give opener a 4333 or 4432 hand with 4 hearts and 15 HCP (to match a 1N-2C-2H start), and game makes ~32% of the time.

Even giving declarer some advantage vs double dummy, those who think this is an invite are correct. Give opener 16 and game makes 48%; 17 and game makes 67%. Seems to me like a straightforward quantitative invitation will work well.

Give opener 4=4=3=2, 3=4=4=2 or 2=4=4=3 and 15 HCP (to match a 1D-1H-2H start), and game makes ~28% of the time. Yes, less than when we don't have any inference about the diamond semi-fit. So, I was wrong when I suggested that the extra bit of information might make bidding game more attractive -- we clearly still want to invite.

Give opener 1453, 2452 or 3451 and 14 HCP and game makes about 36% of the time. Still not worth blasting to game. Increase to 15 HCP and game makes about 54% of the time, so here again a simple quantitative invitation would seem to do well.

Of course, if you have more sophisticated invitational methods, they may work even better.

Thanks for the responses. I guess I could have answered the questions myself with the use of simulation, but I wanted to get a better idea how the field viewed this.

[ArcLight]

Using Deal Master Pro, with 15-17 balanced and 4-5 hearts, 250 simulations:

4H makes 48%
3NT makes 37%

[hrothgar]

NickRW, on Oct 8 2008, 12:30 AM, said:

TimG, on Oct 7 2008, 05:02 PM, said:

Thanks for all the responses.

Recall that the hand is ♠QJT5 ♥KQ43 ♦J94 ♣75.  We were playing weak NTs at the time, so the auction we had actually started 1♦-1♥-2♥, where 2♥ shows 15-17 balanced with 4 hearts (or an unbalanced equivalent).

I don't think that sequence shows 15-17 bal or equivalent. What is partner to bid with a 12hcp 1-4-5-3 shape, for example. I admit partner is likely to have something extra in terms of stength or be unbal.

For what its worth:

I think that there are 12 HCP 1=4=5=3 hands that are too weak to open 1♦. My choice of bids would depend a lot on the specifics of the hand. However, I can easily conceive of any of the following calls:

1. Pass (the most attractive option)
2. 1NT (more attractive with a 3=4=1=5 or 3=4=5=1 shape)
3. 1♥

[TimG]

ArcLight, on Oct 9 2008, 07:17 AM, said:

Using Deal Master Pro, with 15-17 balanced and 4-5 hearts, 250 simulations:

4H makes 48%

That looks consistent with my results. But, I think you want to avoid the trap of thinking that because game makes 50% of the time, you want to bid it. Here an invitation will get you to game when opener has the top end of the range (and game will make more than 50%) and will stop short when he has the bottom end of the range (and game will make less than 50%). That is why I focused on opener's minimum HCP holdings.