It seems clear, to me at least, that if South's
♥9 is the
♠9 then we want to be in spades. So there has to be a way to check for both.
I recognize that my rather simple-minded approach has limitations but I have found it pretty workable. After 1
♦-1
♥-2NT you can easily construct hands where we belong in game in one major or the other, slam in one major or the other, slam in diamonds, and even, although unlikely, slam in clubs. I don't doubt that a well-developed checkback system caan handle all of this, at least I have been told that it can, but I think it needs more, or at least different, features than are needed after 1
♦-1
♥-1NT.
Anyway, for this hand my natural approach works fine. After 2NT-3
♥ we find a heart fit if there is one and we find a spade fit if there is one.
After we find the heart fit, we still have to decide on strain and level. Suppose after the 4
♣ the auction, with different hands, had gone 4
♣-4NT-5
♣(four keys)-5
♦-5
♥ (no
♥Q)-5NT-6
♥(no side king, which is quite possible when South already has shown three aces and the King of trump). Thjen I think we want to be in 6
♥, not 6NT. The hands may be:
Suppose a club lead. 12 tricks will need some very good fortune in NT. 6
♥ is no piece of cake either, but the chances are better. Rise with the ace, diamond ot the King,
♥A, small t
♥K. If the suit splits 3-2 and the Q does not come down, the expected situation, throw clubs on top diamonds, cash the spade ace and lead a spade to my Jack. If it holds, I am making this. Not great, but not horrible, and possibly the
♥ falls under my AK. Not likely, but could happen.
As I see it, with the double stops in the actual hand we can afford to try 6NT. Club lead (for example) taken,
♥K, run the ten. If it loses a club comes back and you go after the spades. If spades don't work either you are going down. It's truew that those in 6
♥ are going down also, but you are going down more Too bad, but probably worth it at mps.