Playing on BBO against random chumps, I pick up the following:
S:Jx H:AKxx D:Ax C:AJTxx
I open 1NT (playing weak NT at these colors), LHO bids 1H, partner bids 1S and RHO passes. I bid 1NT (perhaps a bit heavy. I could bid 2N). Partner bids 2H checking back on my heart stopper and generally forward going. I bid 3N to show the maximum and a doubleton spade. Partner thinks a bit and bids 6 Spades.
(My) RHO leads the Club King. Since I’m on BBO, I can see partner’s hand now (you can set it to see all four as dummy, but I do this so I can think about the play).
Dummy S:Jx H:AKxx D:Ax C:AJTxx
Partner S:AKQTxxxx H:xx D:Qx C:x
Club King led
Partner quickly claims 6. I (mentally) claim 7. RHO really needs the Diamond King and 5 hearts, but even if he only has the Diamond King and four hearts, it’s a double squeeze assuming LHO has the club queen, surely a lock after the opening lead.
Win the club ace, ruff a club high, spade A, then J, ruff a club high (of course, if clubs are 4-3, you don’ t need the squeeze, so we assume theyare 5-2). Diamond ace, ruff a club back to hand and run the trumps. The position on the last trump:
H:AKx C:J H:Jxx C:Q H:Qxx D:K S:x H:xx D:Q
West has to keep the club queen, so pitches a heart. You pitch the club jack, and RHO has to keep the diamond king, so pitches a heart. Dummy is now good. Of course, the actual hand East should really have 5 hearts, so it will be a simple squeeze, but it’s easy to play as a double. In fact, one of the easiest I’ve ever encountered in real life. Practically textbook (and probably unnecessary, unless you happened to be playing in 6 No Trump, where you couldn’t ruff out clubs). But I’m pleased that I saw it almost instantly.
After the hand I ask why partner didn’t claim seven on the double. “It wasn’t worth the time to explain it to them”