[mycroft]

Just one note, as you are in NV, therefore ACBL territory:

The regulation is not that you Alert 1NT-2♣, but that you Alert any further call by responder that may not have a 4cM. Usually, that means 1NT-2♣; 2x-2NT (playing 4-suit transfers), but if you play 3m rebids as "the other 3m hand" (not likely playing 4-suit, but it certainly would exist playing, say, strong direct 3m and 2♠ "bailout in either minor"; now you need a bid for "if you have a fitter, the suit will run and we'll make 3NT". Note, this is *very* old-school; it is much more common to play a 3m rebid after Stayman as (the other) major and longer minor, GF).

Any lowest-club call over NT openers that asks for a major, whether or not it shows one, is not Alertable (although the responses and rebids may be).

Note: All of this is ACBL only.

Having said that, I am a strong believer in "there are no balanced invites" over NT, especially at MPs. I think you are quite safe in playing 2NT after Stayman promising a major (probably the "game if we have a fit, only an invite without a fit" hand) and playing "pass or blast" without. There is a practical advantage (that never comes up): 1NT-2♣; 2♥-2NT; 3♠-p is an auction you can never have with 2NT "may not have a 4cM".