During your first lesson with your new BIL mentor you play some boards against her IAC teammates. You kick their asses as they double most of your cold contracts and fail to double the doomed ones.
At this board, your lazy mentor punts a slam to give herself a coffee break.
Afterwards you can see that most declarers managed to make 12 tricks. But what's the correct play, assuming that diamonds break 3-2? You have 10 top tricks and hearts will give you one more. If RHO has Ax of hearts you have two heart tricks by playing a heart from dummy and duck out the second heart trick, but that's risky. You could rectify the count for a club/spade squeeze against RHO by playing ♥Q from dummy first, which RHO will have to cover, but that breaks hearts as an element in a (3-suited?) squeeze.
So .... should you cash ♣K early? Should you play hearts early? How to decide what to discard on the diamonds? You need four discards, you can spare a spade and a club, probably a heart, but there is no obvious 4th discard.

Help

1♦-(1♠)-3NT-(p)
6NT-(x)-a.p
Diamonds break 3-2 (East has 3) .