…2M = <16HCP, (semi)natural
…2OM = 16+HCP, any hand with 3 of the other major
…2NT = 16+HCP, balanced, no 3 of the other major
…3m = 16+HCP, natural, no 3 of the other major
…3M = 16+HCP, natural, no 3 of the other major
…3 of the other major = 16+HCP, 4 of the other major
2M = <8HCP, 2-3M
2 of the other major = <8HCP, natural, 0-1M
2NT = <8HCP, minors, 0-1M
3m = <8HCP, natural, 0-1M
There are some specific exceptions:
1-1NT-2-2 = <8HCP, 3 (1NT already denied 4) and both minors (5530 or 5431).
1-1NT-2-2-2 = 16+HCP, 4 (showing 3 is useless).
Obviously you can modify this structure a bit, for example use 1-1NT-2-2-2 to show 3-4. As a result, 1-1NT-2-2-3 will now show 5.
You can also use 1M-1NT-2-2-2OM as various handtypes (this saves space!).
If you play Kaplan inversion, it also has implications to rebidding 2OM after a 1 opening.
As usual there are a few (pretty rare) problem hands: <8HCP with 1=4=4=4 and the auction starts 1-1NT-2. Usually it’s best to just bid 2 and hope for the best. Another one is after 1-1, when responder has a strong hand you may have some difficulties.
Playing Gazzilli frees up a few rebids for opener:
– Jump rebids (like 1M-1NT-3m) show a 5-5 with 2 great suits but less than 16HCP. If responder has honours in both suits, 4M in a 5-2 fit can be possible. A typical example is AKxxx-AQxxx opposite Qx-Kxx. 10 tricks are for the taking if both suits behave a little bit.
– 1-1NT-2 shows a minimum hand with 6-5.
– 1M-1NT-2NT: you can use this to show a GF hand with 6M-4m. Since these are difficult to bid anyway, you might as well make it easy using this tool.
In my current 2/1 system we play Gazzilli. The weak version can be with only 2s (5M332 or 4=5=2=2) because we prefer to have our 2 rebid natural with 4+ cards. Only exception we have to the 2 rebid is when we have 4=5=3=1 exactly. Playing 2 or 3 is acceptable since we have true ruffing value. Gazzilli by Frederick Staelens
Source: Free at the Bridge Table
I haven’t posted anything on Gazzilli before. It’s one of my favorite conventions which occurs when the auction starts 1M-1NT or 1-1. It’s a very simple convention with big advantages, few disadvantages, and it comes up frequently.
A 2 rebid from opener is a 2-way bid, showing one of 2 hand types:
– 16+HCP, any distribution
– less than 16HCP, natural (or semi-natural if that fits your system)
Responder has only 1 strong response: 2 shows 8+HCP, any distribution. Any other bid shows less than 8HCP and is natural. In this case a preference should be given to a doubleton Major support.
Opener will now clarify which hand type he’s holding:
– After 1-1/NT-2-2, opener rebids 2M with the weak version. Any other bid shows 16+HCP and makes the auction GF. Bidding 2 of the other major usually shows a 3 card suit, which makes finding 5-3 and 6-2 fits a lot easier.
– After any weak bid, opener will usually pass with the weak version. With 16-17HCP and misfit he’ll also pass. With a very strong hand he can bid a new suit. With fit he can still invite or bid game.
Basic structure after 2:
2 = 8+HCP