After a 1NT-opening many choose to have two ways to show a 5-card major as responder. One way to get to 4H/S vs all hands with 3+ support and one way to offer a choice of games, letting opener pass with 4333 (typically). A normal way to do this is to use a 2-level transfer followed by a jump to 3NT as the "choice"-bid.
What about after a 2NT-opening then? I hadn't reflected much (strangely enough) about that until disaster struck in Holland. This was the deal:
After 2D-multi by RHO, South overcalled 2NT and had to decide what to do after partner bid 3D (transfer) and then 3NT.
The board was played 4 times. At two tables this auction occured and South passed both times for -200, one time East opened 3S instead shutting everyone out (!) for -50 and at the final table East was silent throughout and N-S could relay in comfort to 4H for +620.
After a 2NT-opening space is scarce and we no longer have the luxury of two ways to show our major. How should we handle it? As it is far more frequent that we have a hand wanting to play 4 of a major whenever a fit is found than offering a choice, this should take precedence. The transfer bid of 3D/H followed by 3NT is therefore an asking bid; is asks for support.
No use of judgement from the 2NT-opener is involved any longer; he just looks at his major-holding. With 3 or more, remove to 4H/S even with 4333-shape (may cue-bid with suitable maximum). With 5332 and some useful high cards, the responder could suppress the 5th card and simply check for 4-card support via regular Stayman and play 3NT otherwise, which btw, is what some people do after a 1NT-opening. Fortunately the deal occurred in a practise match.
Next time, we know what to do.
Today I found an article at Larry Cohen's site on this very subject.
How weird. I can't find which date it was published, just listed under 'Recent articles'.
I'm leaving for Montegrotto, Italy, today for 4 days of bridge. Posting resumes Monday.