TWO4BRIDGE, on 2012-March-31, 10:57, said:
Make the ♥Q-ask with 5D.
When it is denied with 5H, then you could bid 5NT, which must be a general "outside Q-ask", since the K-ask ( 5S ) was by-passed.
If he replies 6C or 6D , you can count to 12 tricks at NT.
If he replies 6H, then all he has are 3 bullets and you pray he has some useful Jacks.
..... But 6H may be the better contract since you can ruff a ♦ in the short trump hand ( 3s, 4h, 2d, 2c, 1d-ruff ) .
..... ( But you also need a 3-2 trump split which obviously isn't here according to OP ).
5NT "must be" a queen ask since we didn't make the king ask? So is 6C a jack ask then? I play 5NT as a general slam invitation give the knowledge we are off a keycard and the trump queen. What if we held AKQ Kxx Kxx AJxx here and partner had shown 1? We would probably want to be in slam only if partner has anything extra. If not then 5NT is no worse than 5H.
On the given hand either player could have bid differently but neither would have known for sure 6NT was better by the end. It's good for a serious partnership to have a "choice of 6-suit or 6NT" bid, such as some unplayable suit on the 6 level, but for most partnerships such an agreement would just lead to trouble and I think they are better off doing the best they can on hands like this.