Quite an auction! If I were not playing online, I would check the backs of the cards.
There was something to be said for bidding 6♥. Clearly, partner had a mountain of hearts. I had 2, LHO should have at least 2. It is possible that partner, for his white against red 5♥ call, might have the other 9 hearts. Clearly, both partner and RHO have virtual blizzards but they are bidding at high levels. RHO might have 5-0-7-1 and 6♦ would be a claim.
However, I just could not stomach the thought of taking a sacrifice holding my hand. I passed over 6♦ which, not surprisingly, became the final contract.
I led the ♣K, and saw this dummy:
Scoring: XIMP
(2NT) - 5♥ - (6♦) - All Pass
(2NT) - 5♥ - (6♦) - All Pass
The ♣K held, partner playing the 2 (UDCA) and declarer playing the 10. I was pretty confident that the remaining club would cash, and it did. The ♥A at trick 3 did not cash. This was the whole hand:
Scoring: XIMP
(2NT) - 5♥ - (6♦) - All Pass
(2NT) - 5♥ - (6♦) - All Pass
My partner's 5♥ call really put it to them! +100 was worth 9.21 IMPs. Quite a few pairs made 13 tricks in spades (there were two 2470 numbers in 7♠x making) when partner is on lead after a spade opening bid. In addition to the pair of 2470s, there were 4 1860s (6♠x making 7), a 1660 (6♠x making 6???), a few undoubled spade slams making, and one 1390 the hard way - 4♠x making 7.
Amazingly enough, there were also 7 instances of 5♥x making our way!
The quotient on the board was about +625 EW. So, those pairs that did sacrifice in 6♥ (and one that sacrificed in 7♥) actually won IMPs.
(2NT) - 5♥ - (6♦) - ?