♠ K 6
♥ K J 7 4 2
♦ Q 8 3
♣ K 8 6
♠ 7 5 4 3 ♠ 9 8 2
♥ A Q 5 ♥ 8 8 3
♦ --- ♦ J 9 6 5 2
♣ Q J 9 7 3 2 ♣ 5 4
♠ A Q J 10
♥ 10 6
♦ A K 10 7 4
♣ A 10
Jonathan Steinberg played this deal in a sectional knockout teams in Peterborough ON (hands rotated). West led the ♣Q. Jonathan won the ace in hand and cashed the A♦, getting the bad news. He led another diamond to the queen and advanced the 8♦ which won (covering wouldn't have mattered according to Deep Finesse).
Next Jonathan led the ♠6 to his queen and advanced the ♥6. West took his ace (ducking wouldn't have mattered as long as Jonathan put in the ♥J), and exited with a club, hoping his partner could ruff. The king won in dummy and Jonathan paused to consider the layout.
From the fall of the low cards, it looked like his right-hand opponent had two clubs and five diamonds. Were the majors 3-3 or 4-2? Based on his table feel, declarer decided to play for 3-3.
Declarer led the ♠K and overtook with his ace and cashed the ♠J. He led the ♥10 and overtook with the jack. Next he cashed the ♥K, discarding his good spade to reach a two-card ending. Dummy had a heart and a club, but South had the ♦K 10 sitting over East's ♦J 9.
"Had I played a diamond to the Queen at trick two," said Jonathan, "I could pick up the 5-0 break. But, then there wouldn't be a story to tell!"
The other table played in 3NT, so Jonathan's team won 10 IMPs on the board. One of the players involved said it was a Grand Coup, but that's not the case. A grand coup is a situation in which you trump winners to shorten your trump holding to the same length as RHO. This was an everyday, garden-variety trump coup that you can read about on Wikipedia here or The Bridge World glossary here.
Here's the deal deal presented with BBO's Handviewer: