Yes, I was, for the moment, only looking at 1NT - 4
. For the more general situation I'll just quote from my first post on this thread:
"As with any convention, if you are going to play it you have to agree when it is on and when it is off. I play weekly, more or less, with Carl (not a BBO player). Our agreement is that 4
is gerber if it is a jump made directly after a natural NT bid. So: 1
- 2
- 2NT - 4
is a jump to 4
over the natural rebid of 2NT. That makes it Gerber for us. I have been playing it that way more or less forever, and most everyone I know plays it that way also."
It is certainly the case that others have different ideas as to when 4
is Gerber and when it isn't. In a pick-up game I would probably avoid using Gerber in the auction 1
- 2
- 2NT - 4
. It's true that I play that as Gerber but it does not follow that it would be understood as being Gerber if we have not discussed it. For most players, what we want is a rule that is simple and unambiguous. Must be a jump, and must be directly over a natural NT, this seems simple and unambiguous.
Of course this issue is not confined to Gerber: 1NT - 2
- 2
- 4NT? Natural with five hearts and slam invitational values, in my opinion. 1NT - 4
- 4
-4NT sets hearts as trump and asks for keys. We don't need two ways to do the same thing so 1NT - 2
- 2
- 4NT is natural. Would I be confident with a pick-up partner? No, of course not. If we have not discussed such matters, we should not be surprised when a misunderstanding occurs.
Let me be clear, at the risk of being repetitious. I am not saying that I have presented the correct way to play Gerber, I am saying that with almost all conventions there is no one expert way, no one common way, and really no one right way. So, without discussion, there is apt to be misunderstanding. I think some choices are better than others, but the really bad choice is for one person to be playing it one way and the other person to be playing it a different way.