Hand one:
Scoring: IMP
At my table, east dealing:
1♣ - X - Pass - 1♥
2♦ - 4♥ - 5♣ - 5♥
6♣ - X - All Pass
Of course, 6♠ is ice cold and 6♥ from the heart bidder's side will make. This slam was missed at the other table as well when dealer opened 1♦ and north bid 4♥ in response to partner's takeout double (!). South checked keycards but found out they were off two of them (north didn't show the void) and opponents played 5♥ with an overtrick. Even assuming opponents at my table would sacrifice in 7♣, we lost a bunch of imps on the board for missing slam.
Hand two:
Scoring: IMP
At my teammates table, south dealing:
1♥ - Pass - 2♣ - 3♦
X - All Pass
Best defense will take 3♦ for 800, but teammates dropped a trick and got only 500. Of course either of these is little compensation for the cold 1440 in 6NT (or 1390 in clubs). At my table the opponents were unobstructed and still missed the slam, playing 3NT on a spade lead for 720.
Hand three:
Scoring: IMP
At my table:
1♠(1) - 2NT - 3♦(2) - 5♣
5♠ - Pass - 6♠ - All Pass
(1) This is a normal, albeit minimum, opening in our methods (we play precision+light openers).
(2) Limit or better spade raise.
At the other table teammates did not compete vigorously and N/S played 4♠ making.
Who's to blame on these hands? What should we have done better?

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