[aleatory]

1NT 15-17
Right now we are using 4 suit transfers (1NT-2S=clubs, 1NT-2NT=diamonds, in between bid shows poor fit). I mention this because it has ramifications on the 1NT-2♣-2♥-3♣/3♦ sequence which is the one I am most interested in.

More generally, after 1NT - 2♣ - 2♥:
2♠ -- 4 spades invite? 5 spades invite? if it is the latter then do all invites with 5 spades go through Stayman or just the unbalanced ones? what is 1NT-2H-2S-2NT?
2NT -- if natural invite and the immediate 2NT defined as other then should opener bid 3♠ if accepting invite with 4-4 majors? This shows a lot to defenders if auction goes 1NT-2C-2H-2NT-3S-3NT...
3♣/3♦ -- if natural 5 card suit, does it promise 4 spades? how does opener show a good fit for the minor? can/should opener show 5 hearts?
3♥ -- invite
3♠ -- artificial heart raise? if so, must opener cue? can opener show min or max - perhaps with 3NT, or maybe 3NT=spade cue?
3NT -- natural, 4 spades
4♣ -- splinter? or some ace/keycard ask? I hate to use the g-word here.
4♦ -- if splinter what does it say about heart honors and/or control in unmentioned suits?
4NT -- quant with 4 spades right? -- can/should opener ever sign off in 5♠?

[jallerton]

If you transfer to a minor and then bid another suit, what does that mean?
If it shows shortage with a single-suited minor suited hand, then Stayman followed by 3m should be natural, FG.
If it shows a second suit, then there's less need for Stayman followed by 3m to be natural, so 3m can be used for other awkward hand types, e.g. 3-suiters, raises in Opener's major, Extended Stayman.

[Jinksy]

One of my Ps recently persuaded me to play this as 'to play', on the grounds that it helps with game bidding: with a hand like QJTx x xxx KJTxx, you can start with Stayman, planning to raise 2♠ to 3, but otherwise bid 3♣. At IMPs this seems to lead to a better partial than continuing with 2N, esp since P will often raise it to a hopeless 3.

That said, we play a weak NT (and not 4-way xfers), so slam-chasing is less of a priority for us.