Help
1♠-2♦, 1♠-2♥, and 1♥-2♦ 5+ like a weak two bid, non-forcing (weak and/or lacking a fit)
1M-2♣ 3+ natural, invite+ values, forcing 1 round but not promising a rebid
1M-1N forcing as in 2/1 GF, but could include balanced GF's or GF hands with ♦ and/or ♥s
Background and Motivation for 2/1 NF
But first, why bother? Previous discussions have touched on the general issues -
2/1 theory in a limited bid system, GF, Std, NF, or what?
2/1 bidding in a strong club system, GF, inv (F1 or NF), or NF?
GNAT, Deerfly, Blackfly (some such), A GCC legal MOSCITO variant
2/1 GF is simple to play, but especially in a limited and/or light 1M opening context like precision, GF hands are less frequent. Furthermore, with a limited opener and a weak responder, putting pressure on the advancer with a non-forcing 2/1 bid (like a weak two bid) uses up more space than in standard methods (pass or 1N forcing). Additionally, opener is well positioned to make a blocking raise since responder's suit is known earlier in the auction.
Another point is to discourage preemption in your GF auctions by having some of them begin with an ambiguous (weak or strong) 1NT forcing. In a 2/1 GF auction advancer can often make a preemptive or leading directing bid (e.g. (1♥)-(2♦)-2♠ on KQJxxx x xxx xxx), secure in the knowledge that his partner won't hang him by exploring for game. If instead the auction facing the same advancer was (1♥)-(1N)-?, responder's hand is most often weakish for his 1N response which puts a higher premium on constructive direct bids by advancer and discourages aggressive preemption on what rates to be a part-score hand. When the 2♦ 2/1 GF hand starts with a forcing NT, advancer's weak spade hand gets shut out.
A 2/1 NF System
2/1 NF Continuations:
Over the weak NF responses of 1M-2♦ or 1♠-2♥, uncontested auctions are simple and largely natural. Opener will likely pass, but could make a blocking raise with a fit for responder, or bid 2NT with a forward-going raise. Other suit bids by opener are natural and distributional, scrambling for a better contract with extreme shortness in responder's suit.
The natural invitational+ 1M-2♣ bid:
Most of the hands responding 2♣s are GF hands, specifically -
- any normal 2♣ hand in 2/1 GF (including those with 3M support)
- a GF hand with two suits including clubs (5/4+ either longer)
- a balanced GF hand that would rather have partner declare NT
- an invitational hand with 6+ clubs, possibly with a side suit
1M-2♣-?
2♦ maximum values, establishes GF
2OM natural 4+, minimum (NF)
2M natural 6+, minimum (NF)
2N 4+ ♦s, 1-♣s, minimum (NF)
3♣ 2+ ♣s, minimum (NF)
higher distributional maximums
With an invitational club hand, responder may pass any minimal response or retreat to 3♣. Any other action establishes the GF, allowing the auction to proceed naturally. Observe that this handles 6♣-4OM invitational hands well, with the option to stop in 2M when opener has 6+ suit and a minimum (in contrast to standard auctions 1♥-1♠-2♥-? or 1♠-1N-2♠-? where opener's wide-ranging values often forces an invitational responder to choose an unpalatable 2N invite with (41)26 shape).
Game Forcing hands in 1NT:
In addition to the normal hands included in 1NT forcing, GF hands now included are:
- a single suited GF hand with either ♦s or ♥s
- a two-suited GF hand with both ♦s and ♥s
- a balanced GF hand happy to declare NT
- a GF hand with 3 card support for opener and with less than 3 clubs
1♠-1N-2♣
2♦ 4+ natural GF
2♥ 5+ natural GF
3♣ agrees ♠s (3♠, also implies short clubs)
1♠-1N-2♦
2♥ catchall, hearts or a diamond fit GF
3♣ agrees ♠s (3♠, also implies short clubs)
1♠-1N-2♥
3♣ catchall GF
1♥-1N-2♣
2♦ 4+ natural GF
2♠ 4+ natural GF, also 5+♦
3♣ agrees ♥s (3♥, also implies short clubs)
1♥-1N-2♦
1♥-1N-2♥
2♠ 5+ ♦ GF (could have 4♠)
3♣ agrees ♥s (3♥, also implies short clubs)
The best GF auctions occur when opener rebids 2♣ and there is lots of space at the 2 level for responder to distinguish his various hand types. However, since responder will have either one or both red suits when he holds a GF hand after 1M-1N, it is more likely the opener will have club length and rebid 2♣. This seems like a nice correlation between opener's likely rebid and efficient low-level GF auctions.
Suggestions?
I'm sure there are still issues to work out, but I have done at least some practice bidding with these methods which seems promising. The early values inquiry after 1M-2♣ seems nice, making it more clear to responder whether they should be exploring for merely game or possibly slam. I'll probably be around BBO's practice bidding rooms testing this out if anyone's interested. Comments and suggestions are most welcome!
. In a limited bid system, it's not as critical to stretch to bid something on misfitting weakish hands since game is rare when partner's hand is limited. Often if you pass 1M, advancer will make some balancing action and you might be able to bid clubs later without any ambiguity. That said,