It should be a cause for joy when partner opens one of a major and you have support for the suit. Generally it is right to show this support immediately: the primary case where you may show your own suit first is when you have a game-forcing hand with only 3-card support.
An immediate raise to game is pre-emptive and not a strong bid. It normally shows 5-card support and little else. Occasionally, at favourable vulnerability, it may be made with 4-card support and a weak distributional hand (you would not do it with a balanced, weak hand).
A jump raise, 1M-(Pass)-3M, shows 4-card support and 7-9 points. It is not a strong raise and often described as a mixed raise. You should look at the vulnerability when making this bid: a bland seven points made of queens and jacks may make a single raise when vulnerable.
A single raise, 1M-(Pass)-2M, shows 3-card support and 7-9 points. There is flexibility based on vulnerability: it may be a bad 10 points when non-vulnerable; it may be 4-card support if the hand is very balanced.
With weaker hands and support, you can try the tactical trick of responding one no trump. The one no trump is alertable, since it is wide range but non-forcing, and if asked you should say, “wide range, 5-12 points, may be a very weak raise”.
The 2NT response to 1M is not ‘Jacoby 2NT’. The Jacoby 2NT, as played by the BBO robots, is a game-forcing response guaranteeing 4-card support and is the standard convention used by 2/1 players.
We play a more sophisticated set of responses that allows us to use 2NT for both invitational and game-forcing hands.
We play that the 2NT response is bid with two types of hand:
The response structure is as follows:
1M-(Pass)-2NT-(Pass)
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3♣ any minimum, 10-15 points. This hand may still be good enough to bid game if partner shows an invitational hand. The responder can now bid 3M with an invitational hand or ASK with 3♦. Other bids are game forcing and looking for slam.
3♦ Any 15+ points without shortage
3♥ 15+ points with a club singleton
3♠ 15+ points with a diamond singleton
3NT 15+ points with a singleton in the other major
4♣ 15+ points with 5M, 5 good clubs
4♦ 15+ points with 5M, 5 good diamonds
4M Minimum hand without shortage that would accept invitational
1M-(Pass)-2NT-(Pass)
3♣-(Pass)-3♦-(Pass)
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3♥ 10-15 points with a club singleton
3♠ 10-15 points with a diamond singleton
3NT 10-15 points with a singleton in the other major
4m 10-15 points with 5M, good 5m
4M 10-15 points, no shortage, weaker than immediate 4M
Note that the responses to the 3♦ ASK are the same responses to the original 2NT but with minimum ranges.
If an opponent makes a takeout double of 1M, then we play a standard scheme with
If an opponent bids a suit at the one- or two-level, then we use the following methods:
A one no trump response to 1M is a wide-ranging response and is made on all hands without support or another call with 5-12 points. Over a 1H opener it denies four spades. It is non-forcing but partner should try to find a bid if game is possible opposite a balanced 12 points without primary support.
One of the most inelegant sequences in 2/1 is the following:
1H 1NT wide-ranging, non-forcing
2D (natural) 2NT 10-12 balanced, other suits stopped, invitational
1M - (Pass) - 3m
1S - (Pass) - 3H
Simple jump responses at the three-level show invitational values (10-12 points) with a good 6-card suit and no support for partner’s major (these are hands that are bid 1M-2m-2M-3c in Acol, but in 2/1 this would be a game-forcing sequence).
This is also true of the sequence 1D - (Pass) - 3C.
1C - (Pass) - 2D
1m - (Pass) - 2M
1H - (Pass) - 2S
A jump response at the two-level shows a weak hand with a 6-card suit. Essentially a hand that you would open with a weak two bid.
A double jump response to 1M shows is a splinter bid, showing 4-card support, 0-1 cards in the suit bid, and 10-14 points or 18+ points. Intermediate hands with 15-17 points should respond 2NT or bid their own suit.
On this note, it is good to have a clear agreement with partner about sequences like:
1M - (PASS) - 2m - (PASS) - 2M - (PASS) - 4om = is still most useful as a splinter in om for M, but with limited values and/or only 3-card support
1M - (PASS) - 2m - (PASS) - 2om/2OM - (PASS) - 3OM/4om = it has to be clear which suit this is a splinter for. I think generally it is best if splinters are for the first suit (the suit that was opened originally) and you set another suit by raising it before cuebidding your shortage.
Opener should assume partner has a minimum hand for the splinter response.
Note that 1S - (Pass) - 4H is a SPLINTER. And you need to be on the same page about what 1H - (PASS) - 4S is!
With game-forcing hands without primary support, we normally try to show our distribution first. For example, with 15 points, four spades, five clubs, and 2-2 in the reds, we would respond 2C to an opening 1H and then bid spades later, showing our length in clubs first.
With balanced game-forcing hands without three-card support, you will find that responding two clubs often works best even if it is only a three-card suit. It creates a game force and you can bid no trump on the next round.