[Knurdler]

I am just a club level player and vote for 2C Stayman when 54 in the majors and invitational or better.

If you get a 2 heart or 2 spade reply: if invitational you raise to 3 and partner can pass or go on to 4. If game strength, you raise to 4.

If you get a 2 diamond reply (no 4 card major): if invitational you bid your 5 card major at the 2 level. Partner can pass, bid 2NT, 3NT or raise to 4. This does wrong side the contract but does allow you to stop at the 2 level and to differentiate from game strength.

With game strength, after a 2 diamond reply, you bid your 4 card major at the 3 level (Smolen). Partner cannot pass and must bid 3 of the other major (your 5 card one), 3NT or 4 of the other major (your 5 card one).

The most comprehensive treatment I have found is here:
https://bridge-tips....ding_system.pdf

[mw64ahw]

Knurdler, on 2024-January-21, 08:00, said:

The most comprehensive treatment I have found is here:
https://bridge-tips....ding_system.pdf

Terrance Quested's book was where I started developing my 1NT responses and has a lot of good comparisons.

[blackshoe]

Personally and in general I like the methods presented in Andrew Garnett's Variable Strong NT And The 2♠ Size Ask. It's available on amazon but I'm not gonna provide a link because amazon gives me one that's about three miles long and won't let me shorten it. Not available on The Bridge World or Baron Barclay, I checked. Anyway:

2♣: asks for a four card major. Any strength. Opener shows hearts before spades.
2♦: 5 or more hearts, primary suit, any strength
2♥: 5 or more spades, primary suit, any strength
2♠: range inquiry, either balanced invite with no 4 card major, or 6+ clubs weak or with slam interest, or both minors with slam interest
2NT: 6 or more diamonds, weak or with slam interest
3♣: Puppet Stayman
3♦: both majors, 55 or better, invitational or better
3♥: 1=3=(54) distribution, game interest only
3♠: 3=1=(54) distribution, game interest only
3NT: to play
4♣: asks for aces
4♦: 6+ hearts, game interest, if slam interest the next bid of 4NT is RKCB 0314, suit bids are Exclusion KCB
4♥: 6+ spades, game interest, if slam interest the next bid of 4NT is RKCB 0314, suit bids are Exclusion KCB
4NT: quantitative invite, NF.
5NT: quantitative invite to 7NT, F6NT.
6NT: to play
7NT: to play

With 54 majors either way or 55 majors, weak, start with Stayman, rebid 2♥ over 2♦.
With 4=5 majors invitational, transfer to hearts and rebid 2 spades.
With 5=4 majors invitational, transfer to spades and rebid 3 hearts.
With 54 majors either way and game values, start with Stayman and rebid 3 of the four card major, FG
With 55 majors invitational or GF, start with a 3♦ response to 1NT.

The variable bit in the book title is that he recommends a 14-16 HCP range in 1st or 2nd seat, 15-17 in 3rd or 4th.