This was the last board of a match at the North London club this week, and SB suspected that all was not well. South, Charlie the Chimp, had taken 8 boards to the other table (he did not allow RR, North, to do this as he frequently delivered the boards in error to the duplicate which was also going on) and he came back with 7, as often happens when the match is played in the same room. The other board was brought shortly after. When it was played, ChCh produced an imaginative sacrifice over the East-West slam, which only cost 800. This turned out to only be a flat board, however, as North had bid an unusual 2NT in the other room, and South had no difficulty finding the sac at favourable vulnerability when his partner was known to have a spade void.
SB was not happy. "When you collected seven boards from the other table," he started on the Chimp, "I think you saw that N-S were declaring the contract, or you concluded because North brought you the seven boards, that he was dummy". You managed to work out that the only way you could be declarer was if North had bid an unusual 2NT, as if North had made a weak jump overcall in diamonds, he would have played the hand."
The Chimp was lost for words for once. "I did not get within four yards of the other table, he said. Ask the Toucan, North at the other table. I stood far enough away that I could not see who was declarer".
"I don't buy it," replied SB, "somebody with an appalling reputation for sub-standard ethics such as you could well have bid 7♦ based on UI from another source". "Not so," replied the Chimp, "I just guessed that 7D would be cheap, and RR does not bid when he should as you know."
How do you rule?