[Kungsgeten]

Got some ideas while reading this thread, but did not want to ressurrect it. When opening a natural 1♦ (ours is unbalanced 11--19 hcp), we currently play 2♦ as a simple raise, 2M as non-forcing freebids (8--11 hcp), 2NT natural INV and 3♣ diamond support INV. Jump shifts to 3M are natural and game forcing with 6+ suit. Double has to handle all other hands which want to take action.

Could 2♦ be used as a multi, and double could be a simple raise or some awkward hand? The normal negative double may be to important to give up though.

1♦-(2♣)---
Dbl = Simple diamond raise or INV negative double.
2♦ = Multi. NFB in a major (7--10 hcp) or GF negative double without club stopper.
2M = Natural forcing.
2NT = Natural GF, may have four card major(s).
3♣ = INV+ with diamond support.
3♦ = Mixed raise.
3M = Fit show.

Over the double opener would normally bid 2♦ and responder could then bid 2M (4-card suit) or 2NT to show the negative double. If they bid again over the double I guess advancer would have to double again when holding the invitational hand.

[kenrexford]

To add to your thinking, I am coming to the conclusion more and more, especially when 1D is unbalanced, that 1D-2C-? should be treated as a forcing pass sequence.

[phoenix214]

I think it can get akward if opponent preempts over your multi bid in clubs while you do not know which suit partner has - Like if you rotate it around so that -
2♦ - Hearts NFB or better
2♥ - Spades NFB or better
2♠ - GF takeout with no club stopper
Then you will be better placed in when opp raises higher as there is less uncertainty.

[Zelandakh]

If you do a search you can find Han's method in this spot, which is rather good although it has been a while since I read it. It seems a good idea to use X and 2♦ to show specific majors. I do remember that Han does this the surprising way round (X = spades) and that may well be best. From memory his double guarantees spades but his method could probably be adapted to include a weak diamond raise there. Something like X = 2-level diamond raise or 4+ spades; 2♦ = 4+ hearts; 2M = INV, 5+ suit; 3♣ = good diamond raise ought to be playable and seems to be easier to handle when 4th hand is mean enough to raise clubs.

[straube]

1D (2C)

dbl-simple diamond raise or competitive in a major or invitational without a stopper
2D-stayman
2H-5H, f
2S-5S, f
2N-natural, inv

[Kungsgeten]

kenrexford, on 2016-February-03, 07:41, said:

To add to your thinking, I am coming to the conclusion more and more, especially when 1D is unbalanced, that 1D-2C-? should be treated as a forcing pass sequence.

Yes I read about your idea of this in the other thread. I think it is interesting, and it could probably work. Have you developed the idea further, what would pass show etc? On top of my head it would cool (though probably not very good) to use pass and double as transfers This makes it very hard to penalize 2C though...

1D-(2C)--
Pass = 4+ Hearts. Dbl by opener can be a support double, while 2D denies 3+ hearts.
Dbl = 4+ Spades. 2H by opener can show 3 spades, while 2D denies 3+ spades.
2D = To play
2M = NFB, 8--11. So the transfers above (if having more than a four card suit) are normally weaker/stronger than this.
2NT = Natural INV
Higher = Diamond raise.

[mgoetze]

Kungsgeten, on 2016-February-03, 05:10, said:

1♦-(2♣)---
Dbl = Simple diamond raise or INV negative double.
2♦ = Multi. NFB in a major (7--10 hcp) or GF negative double without club stopper.
2M = Natural forcing.
2NT = Natural GF, may have four card major(s).
3♣ = INV+ with diamond support.
3♦ = Mixed raise.
3M = Fit show.

It seems to me like this does a pretty bad job of finding major fits when responder has less than GF strength, but maybe I'm misunderstanding something. It would be helpful if you could elaborate on what "Natural forcing" means.

[Kungsgeten]

mgoetze, on 2016-February-04, 08:49, said:

It would be helpful if you could elaborate on what "Natural forcing" means.

I'm thinking the same strength and shape that a forcing freebid usually shows, so perhaps 5+ major and (10)11+ hcp?

[kenrexford]

Kungsgeten, on 2016-February-04, 07:10, said:

Yes I read about your idea of this in the other thread. I think it is interesting, and it could probably work. Have you developed the idea further, what would pass show etc? On top of my head it would cool (though probably not very good) to use pass and double as transfers This makes it very hard to penalize 2C though...

1D-(2C)--
Pass = 4+ Hearts. Dbl by opener can be a support double, while 2D denies 3+ hearts.
Dbl = 4+ Spades. 2H by opener can show 3 spades, while 2D denies 3+ spades.
2D = To play
2M = NFB, 8--11. So the transfers above (if having more than a four card suit) are normally weaker/stronger than this.
2NT = Natural INV
Higher = Diamond raise.

Still not sure. I kind of like doible as sort of multi. If weak, I have one or both majors, with Opener expected to pick one (2H hearts, 2D spades). Pass is more flexible, because it allows Opener to rebid a suit or to make a "forced double."

One intriguing idea to me is for Opener to rebid after a "forced double" by bidding like Han suggests, somewhat. Opener doubles with spades, 2D with hearts but not spades, 2H with just diamonds or diamonds plus clubs. That might seem odd, but bidding higher with no major makes sense when Responder doesn't have both majors, strsngely
Still not sure, though.