[MickyB]

I am wondering about using the following responses to a 5+ card, wide-ranging 1♠ opening -

1NT = semi-forcing
2♣ = natural or balanced, GF (balanced/semi-balanced hands will relay out shape)
2♦ = constructive+ with 5+♥
2♥ = 5+♦, GF

I've got good structures for the 2♣ and 2♦ responses, but I'm not sure about the 2♥ response. Any advice on continuations? The only top pair who I know to use this structure are Bocchi-Duboin, who also include single-suited invites in the 2♥ response. Their rebids for opener are -

2♠ = 2-suited without 4♦
2NT = 1-suited without 3♦
3♣ = 4+♦
3♦ = 10+ cards in ♠+♦
3♥ = Balanced with 3♦
3♠ = 1-suited with 3♦, 11-14
3N = 1-suited with 3♦, 15+

The alternative is to put all hands with a primary minor suit into the 2♣ response, and use 2♥ as a 3 card limit+ raise, but that makes the structure after 2♣ a lot more complicated (IMO you need the ability to break the relays when responder is unbalanced).

Thanks

[paulg]

See the AMBRA write up on Daniel O'Neill's site.

Paul

[joshs]

Marc Umeno and I go your 2'nd way:

1S-:
2C: 2/1 in either Minor, starts relays
2D: 5+H 10+ Points
2H: 9-12 ish in support of spades
2S-5-8ish in support of spades

After 1S-2C
We usually break the relays and go natural with
a. a 6 card minor
In some sequences we have a way of showing
b. a 5+ card minor and 3/4 spades

And yes, this all gets complicated.

[david_c]

First comment - which MickyB has already heard me ramble on about - is that the lost step (compared to 1♠:2♦ in natural methods) makes it difficult for opener to describe his hand, but it isn't so much of a problem for responder. The corollary is that even though 1♠:2♥ is not a very efficient sequence, you can't really improve it by taking a few hand types out of 2♥ (unless you go all the way and put all hands with diamonds into the 2♣ relay). Indeed you can probably add a few more hands into 2♥. AMBRA adds weak hands with spade support, for example, and Bocchi-Duboin allow invitational hands with long diamonds. This might not be to your taste, but I think the space is there if you want it.

For opener's rebid, the natural method (which is basically what AMBRA is doing) would be:

2♠ = catchall
2NT = 6+ spades, better than minimum hand (OK this isn't "natural" but it's what Siege uses at the moment and is probably what you'll be doing over 1♥:2♦.)
3♣ = clubs, good hand
3♦ = diamond support, better than minimum
3♥ = hearts, good hand

The big problem you have here is when opener has hearts (the direct consequence of losing the 2♥ step). If opener is minimum with 5-4 shape it's not so bad: these hands work fine in the catchall 2♠ bid. With a maximum 5-4 you're not so well off because a 3♥ bid is very space-consuming. But with a 5-5 shape you have real problems, whether maximum or minimum. The lost step means that you are no longer able to bid hearts twice to show this hand.

You could perhaps make use of opener's 3♠ and/or 3NT rebids:

2♠ = catchall
2NT = 6+ spades, better than minimum
3♣ = 4+ clubs, good hand [but probably better to switch this with 3♦]
3♦ = diamond support, better than minimum
3♥ = precisely 5-4 majors, good hand
3♠ = 5-5 majors, better than minimum
3NT = 5-5 majors, minimum

That at least solves the problem of how to bid a 5-5, but still leaves you a bit short of space. Probably better to switch things around a bit more, making more use of 2NT. Say for example,

2♠ = catchall
2NT = extras, either single-suited or 4+ hearts
3♣ = diamond support, better than minimum
3♦ = 4+ clubs, good hand
3♥ = 5-5 majors, minimum

That looks decent, except that you'd want some artificial continuations after 2NT which adds a lot of complexity.

Bocchi-Duboin's approach is also interesting. They do away with the catchall bid, which helps a lot in trying to show shape but presumably makes it harder to show extras (ie. the usual 2/1 problem).