[genady]

Hello. In systems with strong 2♣opening, there are many conventions with Artificl 2♦ opening bids which have many advantages but all of them have seriouse disadvantage - lose natural preempt with 2♦. I have an idea which simly seem so:
I refer opening 2♣ to be "2 way bid".
1. Weak 2♦.
2. Standard strong opening bid.
Partner accept that opening is weak 2♦ and response is:
2♦ with weak hand.
othwer with strong hand acording partnership agreament (the same rules like after weak 2) - for example more than 10-12 p.
Rebids of Opener:
After 2♦ pass with weak hand or other with strong hand.
After other responses, 3♦ with weak hand or other with strong hand.

Is it posible?

[Cyberyeti]

A number of people play this in the UK, the disadvantages are:

You can't give a standard positive to the strong bid.
You give the opps an extra opportunity with the weak hand in that 6th seat knows he's getting another bid.

Its main advantage is that you can't freely intervene over the strong hand.

[wank]

it's poor because responder can't pre-empt in diamonds.

[rhm]

That is quite common where I play.
Of course there are pluses and minuses.

Freeing up the 2♦ opening for other purposes is a big plus.
Of course when you hold a weak two in diamonds opening 2♣ is not as effective.
To give a positive response only if you have an invitational hand opposite a weak two in diamonds is in my opinion a very small disadvantage since many prefer not to preempt a 2♣ opener anyway with their own suit.

Overall I think the advantages outweigh the disadvantages.

Rainer Herrmann

[Zelandakh]

Here is a write-up on one version of the convention. Note that after a (negative) 2M response the weak hand does not rebid 3♦ but rather passes. This will almost always be a good score if the opps allow the contract to be played undoubled and also creates less disruption to the constructive bidding.