[helene_t]

In for example Precision, I thought that using
1♦-2♣
as the GF relay leaves less space than I'd like, while using
1♦-1♥
as the GF relay makes it awkward to bid the semipositive hands with 4+ hearts.

So I thought that maybe we could let the relay be invitational+, and only a second relay establishes a GF.

We could then make the responses to the first relay be 2-under transfers to allow relayer to show a semipositive flexible hand by accepting the transfer. For example
1♦-1♥
..1♠: 4+ clubs, no 4-card major
....1NT: GF
....2♣,2♦,2♥,2♠: nonforcing
..1NT: 6+ diamonds, no 4-card major
....2♣: GF
..2♣: 4 hearts
..2♦: 4 spades

The the other responses to 1♦ could take care of those semipositive hands that can't safely relay, for example
1♦-?
..1♠: 5+ hearts, forcing
..1NT: 5 spades, nonforcing

(The reason why we need a bid for 5+ hearts is that a semipositive with six hearts can't safely relay, as if it goes
1♦-1♥
2♦
now 2♥ is a relay so there's no way to bid a nonforcing 2♥).

Does this make some sense? I thought it could be reasonably playable if you can live with not having the first relay-break available for asking bids, but maybe it becomes a mess in contested auctions.

[awm]

helene_t, on 2021-May-23, 16:06, said:

In for example Precision, I thought that using
1♦-2♣
as the GF relay leaves less space than I'd like, while using
1♦-1♥
as the GF relay makes it awkward to bid the semipositive hands with 4+ hearts.

So I thought that maybe we could let the relay be invitational+, and only a second relay establishes a GF.

We could then make the responses to the first relay be 2-under transfers to allow relayer to show a semipositive flexible hand by accepting the transfer. For example
1♦-1♥
..1♠: 4+ clubs, no 4-card major
....1NT: GF
....2♣,2♦,2♥,2♠: nonforcing
..1NT: 6+ diamonds, no 4-card major
....2♣: GF
..2♣: 4 hearts
..2♦: 4 spades

The the other responses to 1♦ could take care of those semipositive hands that can't safely relay, for example
1♦-?
..1♠: 5+ hearts, forcing
..1NT: 5 spades, nonforcing

(The reason why we need a bid for 5+ hearts is that a semipositive with six hearts can't safely relay, as if it goes
1♦-1♥
2♦
now 2♥ is a relay so there's no way to bid a nonforcing 2♥).

Does this make some sense? I thought it could be reasonably playable if you can live with not having the first relay-break available for asking bids, but maybe it becomes a mess in contested auctions.

It seems like there are no balanced hands in your 1♦ opening? If this is the case then the scheme you gave seems pretty good. Otherwise it seems easier to use natural rebids like:

1♦-1♥:
... 1♠ = 4♠
... 1NT = 3145 or balanced without a four-card major
... 2♣ = 5+♦ and 4+♣
... 2♦ = 6+♦ no other four card suit
... 2♥ = 4♥ balanced or 13(45)
... 2♠+ = 4♥ unbalanced

The idea is to use 2♥ as a relay after opener's 2♣/2♦ rebids to optimise space, so you need 1♦-2♥ as weak.

[helene_t]

Yeah that's right, sorry I should have mentioned that. I assumed that 1♦ is unbalanced, "natural" including (41)35.

With your scheme, does the 1♥ relay promise hearts if less than GF?

[awm]

My scheme is the somewhat standard “hearts or GF” which allows for other responses natural.

[nullve]

helene_t, on 2021-May-23, 16:06, said:

So I thought that maybe we could let the relay be invitational+, and only a second relay establishes a GF.

This is what Zelandakh does.

helene_t, on 2021-May-23, 16:06, said:

We could then make the responses to the first relay be 2-under transfers to allow relayer to show a semipositive flexible hand by accepting the transfer. For example
1♦-1♥
..1♠: 4+ clubs, no 4-card major
....1NT: GF
....2♣,2♦,2♥,2♠: nonforcing
..1NT: 6+ diamonds, no 4-card major
....2♣: GF
..2♣: 4 hearts
..2♦: 4 spades

The the other responses to 1♦ could take care of those semipositive hands that can't safely relay, for example
1♦-?
..1♠: 5+ hearts, forcing
..1NT: 5 spades, nonforcing

It seems that finding 4-4 major fits can be a problem when Responder has less than invitational values. This is not a problem in Zelandakh's system, where (if I've got the details right)

1♦-?:

1♥ = INV+ relay
1♠ = < INV, 4+ S, may have longer H
...1N = 4+ H
...(...)
1N = < INV, 4-5 H, < 4 S, NF

(But maybe finding the 5-3 heart fit with, say, 12 hcp, 4351 opposite 9 hcp, 2524 is? I don't know.)

Forrester-Gold played an interesting 2/1 system some years ago where (as you can see from their convention card,

1♦-?:

1♥ = "Relay no 5M"
1♠ = "5+♥"
1N = "5+♠"
2♣ = "♣FG or balanced FG"
2♦ = "♥ wk or FG"
2♥ = "♠ wk or FG"
2♠ = "FG 4+♦"
3♣ = "INV"
3♦ = "Mixed"
3M/4♣ = "SPL".

Presumably they responded 1♥ on most (all?) positive hands with a 4c, but not 5c, M. I have no idea what they did over that, but obviously a scheme with 2-under transfers could work, e.g.

1♦-1♥; ?:

2x-2(x!=♠) = 2-under transfer
...2x-1 = INV+ relay
......2x = only non-GF bid, NF
......[2x+1]+ = GF
...(...)
(...)

Or, if you want to keep 2♦ as NAT NF over 1♦-1♥; 2♣, maybe something closer to what benlessard does, in his chapi8 system.

[nullve]

Posting this before overthinking (and not posting) it:

P = normal / <range 0> BAL?
1♣ = <range>, x+y 2-suiter, y longer if x<y / <range 1> BAL / ?
...1♦ = (positive?) relay
......1♥ = <range>, C+O 2-suiter, O longer / ?
.........1♠ = (positive?) relay
............1N = <subrange>, C+D 2-suiter, D longer / ? (=> 2♣ = INV+ relay)
............2♣ = <subrange>, C+H 2-suiter, H longer / ? (=> 2♦ = INV+ relay)
............2♦ = <subrange>, C+S 2-suiter, S longer / ? (=> 2♥ = INV+ relay)
............(...)
.........(...)
......1♠ = <range>, D+M 2-suiter, M longer
.........1N = (positive?) relay
............2♣ = <subrange>, D+H 2-suiter, H longer / ? (=> 2♦ = INV+ relay)
............2♦ = <subrange>, D+S 2-suiter, S longer / ? (=> 2♥ = INV+ relay)
............(...)
.........(...)
......1N = <range 1> BAL
......2♣ = <subrange>, H+S 2-suiter, S longer / ? (=> 2♦ = INV+ relay)
......(...)
...(...)
1♦ = <range>, 1-suiter / <range 3> BAL? / ?
...1♥ = (positive?) relay
......1♠ = C 1-suiter / ? (=> 1N = INV+ relay)
......1N = D 1-suiter / <range 3> BAL? / ? (=> 2♣ = INV+ relay)
......2♣ = H 1-suiter / ? (=> 2♦ = INV+ relay)
......2♦ = S 1-suiter / ? (=> 2♥ = INV+ relay)
......(...)
...(...)
1♥ = <range>, C+O 2-suiter, C longer / ?
...1♠ = (positive?) relay
......<subrange>, 1N = C+D 2-suiter, C longer / ? (=> 2♣ = INV+ relay)
......<subrange>, 2♣ = C+H 2-suiter, C longer / ? (=> 2♦ = INV+ relay)
......<subrange>, 2♦ = C+S 2-suiter, C longer / ? (=> 2♥ = INV+ relay)
......(...)
...(...)
1♠ = <range>, D+M 2-suiter, D longer / ?
...1N = (positive?) relay
......2♣ = <subrange>, D+H 2-suiter, D longer / ? (=> 2♦ = INV+ relay)
......2♦ = <subrange>, D+S 2-suiter, D longer / ? (=> 2♥ = INV+ relay)
......(...)
...(...)
1N = <range 2> BAL
2♣ = <subrange>, H+S 2-suiter, H longer / ? (=> 2♦ = INV+ relay)
(...)

Not sure where to put 3-suiters, 5-5 and 6-6 hands yet. Ideas?

Not sure about the ranges either, but maybe**

<range> = "10+" (meets the rule of 19, say)
<subrange> = "10-15 or 19+"*
<range 0>: empty (but my current preference is actually to pass with 11-13 BAL in 1st/2nd seat)
<range 1> = 11-13 hcp (could be 17-19 hcp in 1st/2nd seat if 11-13 BAL is in P)
<range 2> = 14-16 hcp
<range 3> = 17-19 hcp (could be 20-22 hcp in 1st/2nd seat if 17-19 BAL is in 1♣-1♦; 1N)

?

* Then e.g.

1♣-1♦; [2m-3]-[2m-2]; 2M
1♦-1♥; 2M
[2m-3]-[2m-2]; 2M

could all be NAT with "16-18"

[mw64ahw]

helene_t, on 2021-May-23, 17:07, said:

Yeah that's right, sorry I should have mentioned that. I assumed that 1♦ is unbalanced, "natural" including (41)35.

With your scheme, does the 1♥ relay promise hearts if less than GF?

If it helps I play 1♦-1♠ as GF/GI with the follow-ups below

1NT 3+♦(5+4+3x)
--2♣ 4+♥ 2 under transfers completes with 3
--2♦ 4+♠ 2 under transfers completes with 3
--2♥ 4+♣
--2♠ 5+♦
--2NT 3343 Min
--3♣ 4♥4♠
--3♦ 5♥4♠
--3♥ 4♥5♠
--3♠ 5♥5♠ short ♣
--3NT 3343 non-Min
--4♣ 5♥5♠ short ♦
--4♦ 5+♦ SI

2♣ (444x)
--2♦ Short suit? etc
-- ... 2-suited stronger hands

2♦ 6+♦ not 6430
--2♥ Shape/Strength?
--2♠ 5+♥2+♦ Min
--2NT 5+♠2+♦ Min
-- ...

2♥ 4♥6+♦ Min not 6430
2♠ 4♥6+♦ Min not 6430
2NT 5♣♦ Min
3♣ 4♣6♦ Min
3♦ semi-balanced w/o 3M
3♥ 4♥6+♦ non-Min not 6430
3♠ 4♥6+♦ non-Min not 6430
3NT 5♣♦ non-Min

Subsequent relays further define the shortage/strength

For non-GF hands 1♦
1♥ 4+♥/♠/both or any 3+♣&♦
1NT 4/5♣
2♣ 6+♣
2♦ 5+♦
2♥ 6+♥
2♠ 6+♠
2NT 5+♣♦ Inv
3♣ 5+♦ preemptive or max. with shape