MPs, playing Benj Acol weak NT.
The auction was fine up to the point North rebid their suit at the three level. Wishing to initiate slam investigation I cue bid the diamond control, to which partner cued their heart control. At this point I decided that North must have a lot of spades and for some reason decided not to come in with 3♠ the first time. I put partner with a high chance of a singleton, maybe even a void and it was a 30 point pack with no spade wastage, so I punted 6♣ expecting it to have a fair chance.
This was the full deal:
Two down -200. I didn't anticipate that layout. We even got 75% for this nonsense. Here I was bidding slam expecting a decent chance to make whereas in reality, I was sacrificing against the cold 4♥ the opposition had failed to find which was bid at six tables.