When partner opens 1NT and you know they could possibly have a 5 card major you can jump to 3 as Puppet Stayman so long as you have these requirements:
Responses by opener to 3 are:
Justin Lall wrote a good article about the reasons for using version 2.
3 over partner's 1NT is Puppet Stayman asking for a 5 card major only.
Since we tend to open 1NT with a 5 card major and no other 4 card suit to rebid, a jump to 3 over 1NT with a game forcing hand asks one thing only. Do you have a 5 card major? Opener bids a 5 card major or bids 3, that's it.
This fits in perfectly with our 2 Game Forcing Stayman.
Let me explain.
In our system previously lets's say after partner opens 1NT and we bid 2. We have 5 spades and 3 hearts. Partner responds 2 and we now bid 2 asking partner if they have three card spade support. Now opener's 5 card heart suit will be hidden because bidding 3 would show honor third support for spades and the heart Ace.
Playing the 3 jump over 1NT as Puppet Stayman can be made with a game forcing hand holding one or two three card majors or a 5 card and a three card major.
Opener - 3 4 4 2.
Responder - 5 3 3 2.
1NT | Pass | 3* | Pass |
3** | Pass | 3*** |
* asking for a 5 card major, ** No 5 card major, *** I have one.
Opener's responses: