Diamonds and Rust

Huibertus, on 2026-June-21, 02:31, said:

I like this use of 2 clubs. But surely with such a bid, you have agreed the meaning of all second responses after partner has bid a second time, right?

So what are we trying to do asking what the second bid of this hand should be, why not check your system notes?

I remember our system notes well and summarised them in a post here. They are clear but simplistic and like any agreement need to be interpreted in the context of each hand and auction. What I was trying to do (and partially succeeded, thanks to some thoughtful contributions) is to investigate how others agree the possible bids here and how they would nuance them with my own agreements.

Is it weird to second bid 2NT with a void and fit? Some of my partners think so, even with the same system notes. I thought it would have made sense here, but I'm reassured to hear an expert say the same thing.
Should 3♥ ask for stop? My notes say yes but there may be better uses.
And so on. Heck, my doubts and the related discussion might even be useful to someone else here. That's how Forums work

In general I think most systems, and the players using those systems, are poorly equipped to deal with minor suits. It can be argued that this makes good sense. Major suits are more important and bidding space is at a premium. Focus your system on where the money is. Personally I take a more cynical view: there is plenty of space to have sound minor suit auctions, but the effort it would require is beyond what most partnerships are willing to invest.

Personally I like to give my recommendations starting early in the auction, to show how the inferences cascade through the auction. I don't like the 4+ 1♦, preferring to play an unbalanced one instead, but let's stick with it anyway. Opposite this I would play a response system that looks something like:

Pass: weak any
1M: 4(+)M, F
1NT: 6-11 SF, no 4cM
2♣: [5(+)♣ or 3=3=3=4], GF
2♦: 4(+)♦, inv(+)
2M: 6(+)M, weak (4-8 ish)
2NT: Garbage raise (0-5 hcp, 4(+)♦)
3♣: 6(+)♣, (9)10-11 invitational NF
3♦: 4(+)♦, 6-9 ish ('mixed raise')

Some people prefer to immediately bid 2NT with 10-11 without a 4cM, but I prefer responding 1NT with that hand type.

The 2♣ definition is both natural and a catchall - it is a game forcing bid for hands that have no other good option. However, note that I would not voluntarily bid clubs ahead of an equally long major, and also not of equally long diamond support. Consequently, it must contain 5(+)♣ (with or without an outside 4-card suit) or be exactly 3=3=3=4. In practice I think many people have such lousy inverted minor agreements that they might gain by concealing support and overloading 2♣ with a number of hands with shorter clubs and diamond support - not because it makes theoretical sense, but as a practical consideration.
I understand pescetom's 2♣ differs from the above one. I am curious to hear which hands would bid 2♣ but fail to meet these conditions. It would help clarify the hand evaluation and priorities for opener on subsequent bids.

As a minor aside, I recommend playing this 2♣ as forcing to game. Not 4-of-a-minor, and not 'game-forcing-unless' with exception sequences. The hands that might want to hit the breaks later have alternative bids available on the first round, and the freed up bidding space for stronger hands more than compensates for the losses when we might have successfully diagnosed wanting to stop in a partscore.

So the start was 1♦-2♣. Here I am familiar with several schemes. A lot of them focus on stopper showing and an artificial 2♦ bid to hit the brakes, either limiting strength or promising/denying a certain shape. I much prefer the method pescetom mentions in the post: natural. For me this means:
1♦-2♣; ?:

2♦: 6(+)♦
2M: 4(+)M, unbalanced
2NT: Balanced, may have a 4cM
3♣: 4(+)♣, unbalanced

Jump bids technically do have meaning (3♦ shows a broken 7-card suit, 3M are splinters for clubs - contrast with 3♣ - and 3NT shows a solid 7-card diamond suit) but in practice these rarely come up. The above scheme is not best - not even close. The useful space principle and siding principles both recommend putting the balanced hand in 2♦ instead. Needing a fourth club to raise, when we have a 9(+) card fit or a double minor suit fit, is wasteful if we have slam interest. The jumps have too much overlap with 3♣. It is possible to improve on this scheme by shuffling the bids around and changing the priorities a little bit, but I do think the natural approach is simple and effective.

So we're at 1♦-2♣; 2♠-?. Opener has shown 4♠5(+)♦ (technically a 5♠6♦ hand, or even more extreme, is also possible. I have just been lazy in spelling this out), or perhaps 4=1=4=4 on rare occasion. I would open 1♣ with a 4=1=4=4 pattern, but even if you open 1♦ I believe it is much more practical to call that a system gap and play opener for 5(+) diamonds on this auction. Note that 2♠ denies a four card heart suit. Responder has shown 5(+)♣ or 3=3=3=4. We are in a game force. What should responder's rebids mean?
I believe in both 'support with support' (though I'll introduce exceptions on this very auction below) and 'show shape'. So let's fill in some easy bids:
1♦-2♣; 2♠-?:

2NT: ???
3♣: 6(+)♣, no fit for spades
3♦: 3(+)♦
3♥: ???
3♠: 4(+)♠

Four questions come to mind immediately:

The spade fit is most important. But if responder has both the 6(+)♣ and the 3(+)♦, which bid takes precendece? Sticking with 'support with support', I recommend 3♦ unless your clubs are so fantastic you might wish to probe for a club slam even opposite shortage by partner.
Should 2NT promise a balanced hand? I think here it should not. The bid is cheap and flexible, and responder will frequently not be balanced for the 2♣ response. It is better to reserve 2NT for 'relatively balanced hands' - no fit so far and no extra shape we wish to introduce. On this auction, 'relatively balanced' can be quite unbalanced! Additionally, I think that with 2=3=3=5 or 3=3=3=4 it makes a lot of sense to choose to bid 2NT ahead of 3♦, if we're not too worried about the hearts (and if we are, we may choose 3♦ anyway).
Which hands do not have a satisfactory rebid yet, allocating just the three bids above and using the comment on 2NT? Well, at most 5 clubs, 2 diamonds and 3 spades. We also already mentioned 3=3=3=4 and (332)5. That leaves... exactly 3=4=1=5 and 2=4=2=5. We can either put these in 3♥ or permit bidding 2NT with them. I prefer the latter, but it would not at all be crazy to put these hands in 3♥.
What does 3♥ show? It's a bit of a trick question. We already have a bid for every hand with the scheme above. My general rule for fourth suit bids on 2/1 auctions is that it is a generic punt, asking for further information. Here the punt comes at a very high level, so we want to shy away from using it needlessly. I think the main candidate are hands that are suitable for bidding 2NT in my system, do not have enough diamond support or tolerance to want to mind taking away opener's ability to bid 3♦ on the third round, and are worried about a heart lead. That boils down to hands like 3=3=2=5 with empty hearts. I would rarely make this bid.

I will not go through the entire auction from here. My goal was to show how understanding what options you have, even on a minor-oriented auction, can help clarify choices on subsequent rounds. Make sure your partnership is aware of the agreements and options.

A week ago someone asked me about an auction starting 1♦-2♣; 2♥-?. They were asking for a rebid for responder, but were unable to clarify whether 2♥:

Showed 4(+) cards, or could be stopper-showing in a shorter suit.
Promised 5(+) diamonds (unbalanced), or perhaps 4=4=4=1.
Denied 5(+) diamonds, as all hands with 5(+)♦ rebid 2♦.
Promised extra's, by bypassing 2♦.

Additionally, it was not clear for this partnership whether 3♣ was forcing on this auction. This was a pretty extreme case, but make sure you consider what your bids mean here. A lot of these bids fall in line naturally from negative inferences - e.g. a more common 2/1 2♣ response showing [5+ or 3=3=3=4] - but you need to be aware of this.

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