mycroft, on 2012-January-23, 11:58, said:
So, Cthulhu, what does 2NT show?
Not, "it forces 3♣, after which partner will show her hand", what does it show?
(Yes, I realise it matters what the auction was and what the overcall means. That's part of the problem).
Yes, once you internalise it, it works perfectly, and it's obvious what to bid and what partner showed. But the 2NT bid itself is highly ambiguous, and really difficult to understand, until you do get it.
That's why I like "lebensohl without lebensohl" as I said above. Partly it gets people used to the structure, partly it basically works (without the extra competition, I know, but once they figure it out, it's time to show how to "have one bid mean two things").
Maybe I just don't find the concept of a temporising bid to let partner further clarify his hand type that diffificult. It's not really that complicated, it's conceptually the same as Soloway Jump Shifts where 1H - 2S can show a variety of different handtypes will responder will clarify on his next bid. Heck, even Jacoby transfers work the same way (after 2D, I bid 2H and partner can follow up with 4H with slam intrest, pass with no intrest in anything else, 3NT to offer a choice of games and 3H to invite).
So I temporise in a defined way (in Lebhensohl I bid 3C, in SJS I show side suit shortness if I have it etc), and then responder unwinds his actual handtype.
The most complicated bit is not the 2NT - 3C space save relay, it is remembering to discuss that against Suction you assume the weak single suiter and in transfer methods that your cue bid is the suit they are showing, not the suit they have and you're done.