[JLilly]

When playing a weak no-trump (12–14 or thereabouts), the auction 1♦-1NT (6-10) leaves us doing a lot of guessing. 1♦ can promise 4, or it can be convenient minor, or even promising an unbalanced hand (and thus not a strong NT). If opener has a strong no-trump hand, or really any hand that may want to invite 3NT opposite a maximum, it can be dangerous to do so by a simple raise to 2NT: balanced 16 facing balanced 6 is likely to go down.

Some pairs allow responder to bid 1M with a minimum hand and a fragment, in order to narrow the range of the 1NT response. If you don't want to do that, I propose the following to more accurately assess game values:

1♦-1NT
2♣ = natural (about 11–16) or strong no-trump (15–17). Then,
. . .pass or 2♦ = 6–8, to play. Responder has seven+ cards in the minors and can get us to a reasonable 2m contract.
. . .2M = 9–10, invite to 3N (or possibly 4M) opposite opener's strong no-trump. Fragment / concentration of values. Probably has shortness somewhere. If opener has an unbalanced minimum, we can find our way to a playable fit in 3m.
. . .2N, 3m: 9–10 natural

Opener's rebids are natural, with 3M or 3oM over a non-signoff accepting the game invite. If responder bid 2M, 3M is four cards and implying concern for the other major, looking at 3NT if responder has the other major covered or 4M if not. This can be non-forcing because opener is limited by not having reversed over 1♦-1NT. Nine tricks may be the limit of the hand, with 3M the last contract that makes despite game values.

Is this a common treatment by weak no-trumpers? What do you think? Thanks.

[spotlight7]

JLilly, on 2020-December-09, 14:45, said:

When playing a weak no-trump (12–14 or thereabouts), the auction 1♦-1NT (6-10) leaves us doing a lot of guessing. 1♦ can promise 4, or it can be convenient minor, or even promising an unbalanced hand (and thus not a strong NT). If opener has a strong no-trump hand, or really any hand that may want to invite 3NT opposite a maximum, it can be dangerous to do so by a simple raise to 2NT: balanced 16 facing balanced 6 is likely to go down.

Some pairs allow responder to bid 1M with a minimum hand and a fragment, in order to narrow the range of the 1NT response. If you don't want to do that, I propose the following to more accurately assess game values:

1♦-1NT
2♣ = natural (about 11–16) or strong no-trump (15–17). Then,
. . .pass or 2♦ = 6–8, to play. Responder has seven+ cards in the minors and can get us to a reasonable 2m contract.
. . .2M = 9–10, invite to 3N (or possibly 4M) opposite opener's strong no-trump. Fragment / concentration of values. Probably has shortness somewhere. If opener has an unbalanced minimum, we can find our way to a playable fit in 3m.

. . .2N, 3m: 9–10 natural

Opener's rebids are natural, with 3M or 3oM over a non-signoff accepting the game invite. If responder bid 2M, 3M is four cards and implying concern for the other major, looking at 3NT if responder has the other major covered or 4M if not. This can be non-forcing because opener is limited by not having reversed over 1♦-1NT. Nine tricks may be the limit of the hand, with 3M the last contract that makes despite game values.

Is this a common treatment by weak no-trumpers? What do you think? Thanks.

Kaplan Sheinwald bidders use 1m-1N as 5-8

With 9+ bid the other minor.

[TylerE]

I don't think a 6-10 rebid is really playable opposite that range. Basically you want 1N to max out weak enough that opener can always just pass with the strong NT hand.

[JLilly]

TylerE, on 2020-December-09, 18:09, said:

I don't think a 6-10 rebid is really playable opposite that range. Basically you want 1N to max out weak enough that opener can always just pass with the strong NT hand.

So 1♦-2♣ has to be 9+, may be a fragment if no major? That seems pretty rough.

[helene_t]

This is a well known problem with weak NT systems. It's especially bad in English Acol where you open 1M with the 15-16 4M(432/333) hands.

In 5card major systems it is less of a problem, and even in SA (strong NT) you still have the problem with [4441] and 15-16.

You might consider playing a direct 2NT response as forcing, ostensibly 9-10.

[TylerE]

JLilly, on 2020-December-09, 20:36, said:

So 1♦-2♣ has to be 9+, may be a fragment if no major? That seems pretty rough.

The real solution is to play a strong club system.

Then it's easy.

So, for instance, for me, 1♣ is 16+, 17+ if balanced, 1N open is 14-16, 1!D then 1NT is 11-13. Could flop the 1D and 1N ranges to taste.

[Stephen Tu]

JLilly, on 2020-December-09, 20:36, said:

So 1♦-2♣ has to be 9+, may be a fragment if no major? That seems pretty rough.

No, it's always at least 4+ clubs, as you also have the option of inverted raise on 9+ with diamonds. So the worst situation is 3334 shape. You'd have to structure rebids so that 2c bidder can rebid 2nt NF opposite min unbal.

Alternately, if you prefer 1d-2c as GF, you can do things like:
(1)1d-2nt = 9-11, opener expected to pull if weak unbal
or
(2)1d-2H = art. multi-way JS, 2s asks, include 9-11 nts, maybe a mixed raise of diamonds, maybe strong jump shift hearts.
if you prefer to keep 1d-2nt as GF

Doing it this way is way less rough than 1d-1nt could be 10 count and you have 16 and no idea what to do.

[JLilly]

Stephen Tu, on 2020-December-09, 22:08, said:

it's always at least 4+ clubs, as you also have the option of inverted raise on 9+ with diamonds. So the worst situation is 3334 shape.

Inverted on a 3343 9-count is its own problem, yeah? May well get you too high opposite a minimum opener, and you have less safety to use bidding space to investigate sensitive games or slams.

[DavidKok]

It sounds like you're stuck between a rock and a hard place. With both the opening hand and responder still being rather wide-ranged it is impossible to both sensibly stop in 1NT and explore games. The other commenters have suggested limiting responder by shaving off the top of your 6-10 NT reply. Alternatively, you could try to limit opener, for example by playing some flavour of balanced club and unbalanced diamond.

Regardless of which solution you choose this will be a systemic weakness of the weak NT. If you change nothing it will be a rebid problem, if you swap to a (let's say) 5-8 1NT response you will be behind the field on 1♦-2♣, and a balanced club comes with its own laundry list of questions. I would recommend whichever option you and your partner are most comfortable with, since most of these just shuffle the problem around.

[nullve]

TylerE, on 2020-December-09, 22:06, said:

The real solution is to play a strong club system.

Or just

1♣ = natural or 15-20 (14-19?) balanced
1♦ = natural, unbalanced
1N = 12-14 (11-13?)

with the right kind of T-Walsh.

[Stephen Tu]

JLilly, on 2020-December-10, 01:18, said:

Inverted on a 3343 9-count is its own problem, yeah? May well get you too high opposite a minimum opener, and you have less safety to use bidding space to investigate sensitive games or slams.

It's not THAT bad. The main problem is a tendency, without doing some fancy rebids, to play 15 bal opposite 9 bal in 3nt. This is sub-optimal, but some of them make.

- If opener is minimum unbalanced, it should be pretty easy to stop in 3d. It's unlikely that an alternate sequence would let you buy the contract lower (opps tend to have bid already or balance).
- If opener is strong and going to game/slam, responder is really only a point lighter than std inverted, IMO you can account for this.

If it really bothers you then make a T-walsh system like nullve says.

[AL78]

When playing a 4CM weak NT system, 1X - 1NT is 6-9 HCP, opener with a balanced 15-16 passes, bids 2NT with 17-18 and bids 3NT with 19 (if not opening 2NT on 19-20 HCP). The number of times a game is missed with a maximum 1NT response opposite a balanced 16 is so small it is not worth worrying about. With a 10 count opposint a 1suit opening I will bid a suit at the two level if I can't show a suit at the one level, so 1♦ -(P) - 2♣ is 10+ HCP, at least four clubs.

[Zelandakh]

I thought it was fairly standard for 2♣ to be made on hands that are willing to play game opposite a balanced 15 and for 1NT to be less than that. The real problem hand is then 4441♣, which you either have to open 1♥, make 1♦ - 2♣; 2♦ forcing, or be prepared to finish in some silly contracts from time to time.

[JLilly]

Stephen Tu, on 2020-December-10, 06:17, said:

[I]nverted raise on 9+ with diamonds. . .is not THAT bad. The main problem is a tendency, without doing some fancy rebids, to play 15 bal opposite 9 bal in 3nt. This is sub-optimal, but some of them make.

It seems like there might be a case for compromising only one of 1♦-2♣ and 1♦-2♦. Keep 1♦-2♦; 2NT as 15-17 FG without getting too high on the 15-facing-9 deals, and put the 9-HCP 33(43) hands both into 2♣.

Zelandakh said:

I thought it was fairly standard for 2♣ to be made on hands that are willing to play game opposite a balanced 15 and for 1NT to be less than that.

Responder still has only two buckets below a game-force, it's just 6–9 and 10–12 now. (If 1♦-2NT isn't 11–12 rather than GF.)

Zelandakh said:

The real problem hand is then 4441♣, which you either have to open 1♥, make 1♦ - 2♣; 2♦ forcing, or be prepared to finish in some silly contracts from time to time.

Right, if a 2♦ rebid is any minimum, NF, then you end up in a silly 4-2 fit when both hands are minimums and opener is 4441 and responder is 3325. This requires two exact hand shapes, and so it should be less likely than ending up in a probably-bad 3NT whenever it's a balanced 15 facing a balanced 9.

I suppose an alternative is to use 1♦-2♣; 2♥ as either a natural reverse or exactly 4441, the latter à la Kokish, even though Kokish allows responding 1M with only three for weak responding hands and so he doesn't need 1♦-2♣ to be on as little as 9 HCP. Responder with a minimum balanced hand bids NF 2♠, and you end up there with a 4-3 fit, unless responder is exactly 2335 and has to decide whether 2NT or 3♣ is less bad. But this just shuffles the silly contract around, compromises the 2♥ rebid, and doesn't give opps the chance to balance with an unfortunate (for them) 2M.

[Tramticket]

This is a problem for a weak NT system. The 6-10 range is surely too wide. As an Acol player the range is 6 up to a poor 9 and this still feels too wide at times. Opener will pass with a balanced 15, invited with 17-18, but 16 is a difficult case. Most of the time I pass with 16, but that is risky if playing teams and vulnerable!

Note that a 1NT response has different problems if responder hold a balanced 6-9 and you play 1NT as forcing or (the linguistically challenged) semi-forcing. There are no choices that can solve all of the hand-types.

Opening 1D with 4441 and a singleton club is one of those theoretical problems, which never seems to be a problem in real life. I open 1D and very occasionally I rebid 2D on a 4-card suit, but the auction never seems to end there. Maybe one day I will have to play 2D on a 4-2 (Or even 4-1!) fit and when that happens, I will just have to take my medicine. It will be a small, part-score disaster.

[Douglas43]

Zelandakh and Tramticket summed it up pretty well for me. The 1NT response on 6-10 has a wide range. That is driving you to make a move on 16 counts. Playing 6-9 with the option to upgrade good 9's makes opener's life easier

1D-2C(9+)-2NT is GF so you might be in game with 15 opposite a good 9 if both minimum, and 1D-1NT-pass might be 16 opposite bad 9 occasionally. But all that means is that you bid a few borderline games and miss a few.