[firmit]

This bidding sequence came up tonight (simple enough): 1NT-2NT*

The alert was: bad doubleton
He held:

xx
Ax
AJ8xx
A10xx

Openers responses:
3NT if no slam interest
3C asks
- 3D hearts
- 3H spades

Guess the criteria is slam interest with the minors or looking for 6NT holding 2245 or alike... somebody care to comment? Is this widely used? It should be said that 1NT-2♠ is also used as minor suit investigation - I see some redundancy..

[hrothgar]

I know a number of systems in which 2NT asks for a weak doubleton.
I don't see the merit in showing one...

For example, the Scanian NT structure uses 2N to ask for a weak doubleton. This bid is used as either

1. Anti-Lemming
2. A way to determine whether a long minor with two top honors is likely to run

The Scanians couple this with a 2♠ bid that asks responder to show a 4 card major with a maximum hand. Responder holds either

1. A slam oriented hand with both minors
2. Weak with both minors
3. Weak with long Diamonds
4. Game invitational strength with no 4 card major

[david_c]

hrothgar, on Jan 9 2008, 11:38 PM, said:

I know a number of systems in which 2NT asks for a weak doubleton.
I don't see the merit in showing one...

Why not? If you want an anti-lemming bid, isn't it better to tell the opponents about dummy's weakness rather than declarer's?

[hrothgar]

david_c, on Jan 10 2008, 02:05 AM, said:

hrothgar, on Jan 9 2008, 11:38 PM, said:

I know a number of systems in which 2NT asks for a weak doubleton.
I don't see the merit in showing one...

Why not? If you want an anti-lemming bid, isn't it better to tell the opponents about dummy's weakness rather than declarer's?

All other things being equal, yes...

However, all things are not equal

1. I don't see any way that this anti-lemming bid can be profitably combined with other hand types
2. I think that hands suitable for this bid are too rare to justify the use of bidding space

[cherdano]

I have played a NT sytem with asks for a weak doubleton after Stayman. The purpose is to avoid bad 3N contracts that would make half the time when opponents don't find the right lead, and instead play 4m or 5m going down as well.
(Yeah I am exaggerating but it is really not clear to me that they are useful.)

[kfay]

I use a NT structure that involves figuring out whether or not vulnerable suits are involved. To me this structure is hitting on the right idea's ugly cousin.

The idea that 2NT promises a weak doubleton is misled. I'm not saying that I know what the solution is but here's the system that my partner and I employ.

1NT-2NT is game forcing. Over this opener has several options:
 * 3♣ asks responder if they have a weak doubleton
  - 3♦ says you have a weak doubleton in a minor
   -> 3♥ asks
    ->> 3♠ shows club doubleton
    ->> 3NT shows diamond doubleton
  - 3 of a major shows shortness in that major
 * 3♦ is staymanish
  - responder, if they have a 4-card major, bids the OTHER
 * 3 ♥/♠ shows a 5-card suit
 * 3NT is to play

If you're playing that 2NT guarantess a small doubleton it seems to me that if you're not going to be playing 3NT that there's some better place to play than 2NT. So this system seems a little odd to me.

I've found that there's ample room to include all minor-suit transfers and balanced-invites (ask if you want me to go into more detail). We've had great success with this structure considering it doesn't come up all too frequently.

[benlessard]

I think showing a weak doubleton is paying mostly be when the hand with the weak doubleton has 3 in the other M so 4M is a real possibility. Showing a weak doubleton with hope of making 5m or stopping in 4m isnt likely to pay that much.

[kfay]

benlessard, on Jan 10 2008, 12:49 AM, said:

I think showing a weak doubleton is paying mostly be when the hand with the weak doubleton has 3 in the other M so 4M is a real possibility. Showing a weak doubleton with hope of making 5m or stopping in 4m isnt likely to pay that much.

Yes. The biggest successes I've had have been playing in the 4M moysian.

[zasanya]

The power precision 1NT structre has something similar


2S :: [minor suit stayman] relay to 2N, promises (45) in minors
2N : 3C :: 5+5+ minors, 0-9 HCP
3D : to play
2N : 3D :: 5+5+ minors, 10+ HCP, forcing to 4m
2N : 3H :: 31(45), 10+ HCP
2N : 3S :: 13(45), 10+ HCP
2N : 3N :: 22(45), 10-13 HCP, both doubletons weak
2N :: relay to 3C
3C : P :: 6+ clubs, obviously to play
3D :: 6+ diamonds, sign-off

3H :: 40(54), 8+ HCP
3S :: 04(54), 8+ HCP
3N :: 22(54), 14-15 HCP, both doubletons weak
4m :: 5+, balanced, 15-16 HCP

[P_Marlowe]

Hi,

I doubt that this convention makes a lot of sense,
at least the way you have described it.

Opener should be able to judge if it is a good idea
to look for slam, just because responder has xx in
a suit?
This can only make only sense, if responder promises
additional features, e.g. he can only make this bid with
a (semi) bal. shape and values sufficient for a quantitative
4NT. => The alert would be fairly incomplete.

Assuming that this is the case, I would say the frequency
of the 2NT bid is fairly low, and you may use this bid for
something more frequent.

With kind regards
Marlowe