[helene_t]

When you open a natural 1NT, you don't use all the bidding space you have, and nevertheless you have more accurate auctions than after other openings. OK, maybe you belong to the small minority that has defined all the 3-level responses in a non-redundant way, but you don't use them more than once every other year and you could easily live without them.

So I thought of putting an extra option in the 1NT opening to take the load of the two-openings.

1NT=15-17 bal OR 0-7 points with a 6-card hearts.

Responses:

2♣: Asks for a 4-card spades and for the weak variant, but not for a 4-card hearts in the strong variant. Includes most hands that have a positive response opposite the weak variant without fit.
2♦: Transfer, opener has a specific superaccept for the weak variant.
2♥: To play opposite the weak variant but opposite the strong variant it is ostensibly a transfer to spades. So mostly 0-17 points with 5+ spades.
3♥: Barage opposite the weak variant but GF opposite the strong variant. So ostensibly 9-16 points with three hearts (or Hx), but we can use opener's 3♠ bid for something, maybe catering to responder having 44 majors, or maybe catering to short spades?
3NT: four hearts, 9-17 points

2♠...3♦ and 3♠ to patch various holes.

[nullve]

A similar opening:

https://www.bridgeba...8461-multi-1nt/

The standard 1N opening in 1st/2nd seat seems rather overloaded to me if partscore hands are to be treated with the respect they probably deserve, so I'm happy I've found a way to avoid opening 1N with 22(54) in my system so I no longer end up in 2M on a 4-2 fit (or, alternatively, 3m on a 5-2 fit) after Crawling Stayman.

But I agree that 1N in 3rd/4th is probably underloaded (at least in my system) and recently I've actually been toying with an opening structure in 3rd seat that includes

1♣ = either strong or a hand sith subopening values (but 8+ Milton Work points in order for the system to be non-HUM) that is not suitable to open 2♣+ with
1♦ = a MIN Precision 1♦, 2♣ or 2♦ opening
1N = 14-16 BAL or a MAX Precision 1♦, 2♣ or 2♦ opening
2♣+ = "preempts".

[nullve]

helene_t, on 2021-January-24, 15:12, said:

So I thought of putting an extra option in the 1NT opening to take the load of the two-openings.

1NT=15-17 bal OR 0-7 points with a 6-card hearts.

Or maybe

1N = 15-17 BAL or Intermediate 2♥,

which is not a brown sticker and would free up the 2♥ opening for lots of Swedes.

[helene_t]

nullve, on 2021-January-24, 17:04, said:

1N = 15-17 BAL or Intermediate 2♥,

Yeah maybe. Of course it's a practical consideration that your system is legal in your jurisdiction

But if the 1NT opening can be unbalanced, 1NT can be a silly contract, so I wanted to make sure that whenever we end up in 1NT with a 10-card fit in hearts, opps will have 26+ points so we don't worry about undoubled downtricks. If we can play a silly 1NT with 11+7 points, we may be heading for a poor score. Maybe only play such a system when nonvulnerable?

[helene_t]

nullve, on 2021-January-24, 16:38, said:

A similar opening:

https://www.bridgeba...8461-multi-1nt/

Dammit, Kungsgeten obviously got this idea before me

[helene_t]

I was thinking about a defense against this multi 1NT.

The multi 1NT opening seems playable in uncontested auctions, but it has weaknesses in contested auctions, so let's try to exploit that.

If we use a natural 2♠ overcall against the multi 2NT, the multi 1NT players could play something like:
1NT-(2♠)-
x=optional double without heart tolerance, typically 31(45) with 9+ points or so.
2NT=lebensohl, ostensibly a weak hand with a long minor and tolerance for hearts. Could also be a weak hand with hearts
3♣=4-card hearts, 9+
3♦=hearts, 8+ points
3♥=9-16 points or so, to play opposite the weak variant with hearts.

The weakness of this is that it doesn't work if opener has a weak hand with spades. So let's define the 2♠ overcall in such a way that responder can't make assumptions about opener's hand.

We could play canape:
(1nt)-
x=penalty, 15+ points
2♣ 6+ in a major, wide rangring
2♦ 5 in a majors and 4+ in a minor
2M= canape, 3-4 cards

[DavidKok]

I know a pair who exploit the fact that pretty much any defence is legal against NT. They play every overcall as "long or short in the bid suit", showing either 5+ and to play or 1- and support for all other suits. I think this type of garbage would do very well against your creative 1NT, you have no chance to ever find who holds what.

In general I prefer playing conventional nonsense without anchor suits against these ambiguous openings. If I had the time to discuss this with my partner beforehand I would suggest a defence along the lines of:

• X is 13-15 bal
  
• Any 2-level bid is either the suit above that or the two suits above that one
  
• 2NT is any two-suiter that cannot be shown via this scheme

I believe this is not a good structure against a natural NT, but if you start diluting the meaning responder will not have safe calls available. So we typically get enough space to show our hand. Or to put it differently: when nobody knows what is going on, it's just poker disguised as bridge.

[nullve]

Whatever opps 1N defence is, we should never be in a worse position after

1N-(2x)

than after

(2x).

So we might decide to defend as if we had we forgotten we already have opened 1N!

I've already been thinking about using the same idea (=: Principle of Amnesia? ) in similar situations in my own system, just to simplify things.

[DavidKok]

nullve, on 2021-January-31, 09:28, said:

Whatever opps 1N defence is, we should never be in a worse position after

1N-(2x)

than after

(2x).

So we might decide to defend as if we had we forgotten we already have opened 1N!

I've already been thinking about using the same idea (=: Principle of Amnesia? ) in similar situations in my own system, just to simplify things.

While in general consistency across different possible auctions is very good, the claim as stated is false. The point is that the opponents are likely to play their 1NT-(2X) bid as something different from a (2X) bid - for example, it may very well be a destructive bid showing shape but not strength. This is practically unplayable if the hand is likely to belong to the overcaller's side, but quite safe over 1NT. Also if partner has just opened 1NT they will often assume that you, as responder, will take captaincy of the bidding, so you are often forced into action on a hand that would pass over (2X) (regardless of what that bid means).

[helene_t]

Haha principle of amnesia, I will put that in the "general approach" field of my cc. It's always difficult to figure out what to put their if we play a weird system.

[helene_t]

Btw David, nullve suggested amnesia when we open a multi 1nt which doesn't suggest that the board belongs to us. I suppose he wouldn't play amnesia when we play a normal 1nt opening.

[nullve]

If the 1N opening is as in the OP and the bidding goes

P-(P)-1N-(2x),

maybe Responder (to the 1N opening) could assume 15-17 BAL and be right almost every time even when holding a near-opening hand himself.

[Kungsgeten]

helene_t, on 2021-January-24, 17:28, said:

Dammit, Kungsgeten obviously got this idea before me

I actually got to try my version of the multi 1NT once in real play. It was a lot of fun, and as you've said in this thread I think the main downside is when they interfere. The system played was this: http://www.snortingm...atdiamond2.html
Another version with relays: http://www.snortingm...raldiamond.html