[awm]

mikl_plkcc, on 2025-May-13, 11:30, said:

To follow up, what is the level of force in different natural systems after a 2/1 response?

Obviously, in 2/1 game forcing, it is game forcing, but there are variants like forcing to 3NT (i.e. can stop at 4m), or a suit rebid cancelling the game force.

Are the following sequences forcing in different natural systems around the world? Please tell me in which system(s) the following are forcing, and if so, the extent of force:
1♥-2♣-2♦?
1♥-2♣-2♦-2♥?
1♥-2♣-2♥?
1♥-2♣-2♥-2♠?
1♥-2♣-2NT?
1♥-2♣-3♣?

1♥-2♣-2♦ is pretty universally played as forcing in all systems I'm aware of. It's definitely forcing in standard american and SAYC.
1♥-2♣-2♦-2♥ would normally not be forcing if you don't play 2/1 GF. There is some debate as to whether it's a simple preference or shows a three-card limit raise. It's definitely not forcing in standard american or SAYC.
1♥-2♣-2♥ is forcing in standard american and SAYC. It's not forcing in Acol. Not sure about all other systems.
1♥-2♣-2♥-2♠ is pretty universally at least a one-round force. It's definitely forcing in standard american and SAYC. Normally I would play this as forcing to game but I think that's pretty unclear in standard american or SAYC.
1♥-2♣-2NT is forcing in a strict interpretation of SAYC (responder promises a rebid) but most standard american players treat it as NF.
1♥-2♣-3♣ is also forcing in a strict interpretation of SAYC (responder promises a rebid) but most standard american players treat it as NF.

[mw64ahw]

awm, on 2025-May-13, 12:01, said:

1♥-2♣-2♦ is pretty universally played as forcing in all systems I'm aware of. It's definitely forcing in standard american and SAYC.

If 2♣ can be invitational in ♦ or GF then opener bids 2♦ unless ok to accept the invite. Then responder can Pass with the invite