I was North on this hand - pairs MPs:
But this doesn't tell the whole story. On the first round I bid 1♣ (!) . My excuse was, I was half-asleep, I thought West was dealer, and I genuinely hadn't noticed my partner's 1♥. We play Acol with three weak 2's, and I was under the impression I was opening 1♣ hoping to elicit a response of some sort from partner.
I woke up alright when I heard West (who is a qualified TD himself, though he wasn't TD'ing this session) explaining to his partner that she had the option to accept the 1♣. She declined, so he then turned to me and explained that I must correct my bid, but if I bid anything other than 2♣ he would summon the acting TD, with dire penalties...
Of course I amended my bid to 2♣ - even if it wasn't quite the correct bid. I knew what the Law says and I wasn't about to 'silence' my partner - not with a possible slam on!
Once my partner jump-rebid his ♥ I was keener than ever on the slam, of course - but you can see what happened next. My partner - possibly a bit confused by my earlier insufficient bid, gave the wrong response to 4NT. We play 0314 so he should have bid 5♣ - whereupon I would almost certainly have gone to 7♥ or 7NT. I could see at once that his response was wrong: it couldn't possibly show 2 keycards + Q trumps, seeing as I had the Q♥! My guess was, he meant to bid 5♥ showing 2 keycards minus Q - but I was boxed into bidding 6♥ and settled for that. In our club we don't normally Alert after a natural bid at three level or above.
As you can also see, 7♥ and 7NT are virtually cold. On a ♦ lead, it's laydown provided ♥ are not 4-0, and they weren't. But 6♥ +1 seemed a reasonable outcome.
As it turned out, no-one bid the Grand. Two tables reached 6NT +1, so we had to settle for 71%.
The opponents didn't ask for any adjustment - just as well. They might have had a case - after all my insufficient bid had given partner UI that I had an opening hand....
Moral: I must try and keep more awake, next session!