My partner held this opposite my 2NT (20-21) opening, At the table she transferred to spades and then bid 3NT, which I passed, having only the Ax of spades. We missed our 4-4 heart fit, and there are 11 easy tricks at hearts when the diamond finesse works and East has KJx of spades.
With our current agreements, 3♣ is Puppet Stayman, so we would have gotten to 4♥ if that is what she bids. But can we get to 4♠ if instead of the actual hand, I have 3 spades and 3 or 2 hearts, but play safely in NT when I hold fewer than 3 spades? Or is this just one of the shortcomings of puppet Stayman? (You give up something to get something.)