[paulsim]

Hi folks,

A.-
1D p 1S p
1ST x ?

2C is still NMF?

B.-
1D p 1S (x)
1ST p 2C is still NMF?

C.-
1D (x) 1S p
2C p 2H is still 4SF?

D.-
1H p 1S (x)
2C p 2D is still 4SF?

E.
1D p 1S (x)
2C p 2H is still 4SF?

F.
1D p 1S p
2C (X) 2H is still 4SF?

Thanks,
Kind Regards
Paul_S

[smerriman]

I can't see why I'd want to give up all my usual methods for searching for the best contract just because an opponent doubled at some point.

[bluenikki]

paulsim, on 2022-August-19, 08:39, said:

Hi folks,

A.-
1D p 1S p
1ST x ?

2C is still NMF?

B.-
1D p 1S (x)
1ST p 2C is still NMF?

C.-
1D (x) 1S p
2C p 2H is still 4SF?

D.-
1H p 1S (x)
2C p 2D is still 4SF?

E.
1D p 1S (x)
2C p 2H is still 4SF?

F.
1D p 1S p
2C (X) 2H is still 4SF?

Thanks,
Kind Regards
Paul_S

In each case, you're bidding an opponent's (alleged) suit. So there is all the more reason for it to be forcing. But it is not clear that you can retain the same response structure.

By the way, what did opener's bid of an opponent's suit mean? As in C, D, and E.

In F., doubler has supposedly shown diamonds and hearts. Are diamond bids in the later auction forcing?

[pescetom]

smerriman, on 2022-August-19, 14:12, said:

I can't see why I'd want to give up all my usual methods for searching for the best contract just because an opponent doubled at some point.

And if you want to convince me to do so, at least post hand diagrams

[Gilithin]

A. If XX is business, then it makes sense for 2♣ to be weak and natural, particularly if you allow light responses in the modern style. If XX is a rescue then 2♣ is going to be a forcing relay.
B. If 1NT denied 3 spades then I am not really sure what this 2♣ rebid should be. But in some other similar auctions things are less clear so I would expect NMF to be on by default. If 1NT does not deny a 3rd spade then not playing it NMF here when that is the agreement without a X would be weird.
C-F. I canno think of any reason not to play 4th Suit Forcing as artificial in these auctions.

[helene_t]

Gilithin, on 2022-August-20, 07:36, said:

A. If XX is business, then it makes sense for 2♣ to be weak and natural, particularly if you allow light responses in the modern style. If XX is a rescue then 2♣ is going to be a forcing relay.
B. If 1NT denied 3 spades then I am not really sure what this 2♣ rebid should be. But in some other similar auctions things are less clear so I would expect NMF to be on by default. If 1NT does not deny a 3rd spade then not playing it NMF here when that is the agreement without a X would be weird.
C-F. I canno think of any reason not to play 4th Suit Forcing as artificial in these auctions.

Agree with all this with the possible exception of F. Here, it would make some sense to play xx as the generic force (i.e. instead of FSF) and play 2♥ as weak with 5-5 in the majors.

[thepossum]

Sorry but the OP lost my interest immediately
You need to be able to sell a Bridge query

[mikeh]

paulsim, on 2022-August-19, 08:39, said:

Hi folks,

A.-
1D p 1S p
1ST x ?

2C is still NMF?

B.-
1D p 1S (x)
1ST p 2C is still NMF?

C.-
1D (x) 1S p
2C p 2H is still 4SF?

D.-
1H p 1S (x)
2C p 2D is still 4SF?

E.
1D p 1S (x)
2C p 2H is still 4SF?

F.
1D p 1S p
2C (X) 2H is still 4SF?

Thanks,
Kind Regards
Paul_S

Bearing in mind that new minor forcing, as used in these examples, is rarely played by strong players (2C as a puppet to 2D, to play or to show invitational values with the next call, and 2D as an artificial gf are fairly standard these days), my answer to all of these is ‘yes’.

For A, the only one where I think there may be a reasonable argument, I’d take redouble as emphasizing that (1) we’re making 1N and (2) we’re hunting for a penalty if they run. Thus one still has a need for new minor if responder’s hand suggests looking for our own contract rather than penalizing the opps.