Scoring: MP
I am pleased to admit a tad bit of a poorly-placed grimace from this evening. South opened 2NT. I passed. North bid 3♣ Stayman (yes, he did), and partner passed. South responded 3♦, and north ended the auction with 3NT.
Of course this is strange, but the play is the thing. On lead, I hated all options, electing in doubt to lead fourth best from longest and strongest. This worked out decently, as you can see.
Declarer won a high club, finessed the heart, and then casked two more hearts (discovering the 3-2 split), ending in dummy with two remaining hearts. He then took an unsuccessful spade hook, and I was in again.
After counting out Declarer's hand (20-22 range), I decided that he held one, but not both, diamond top honors. So, it seemed safe to lead a diamond. Partner, a rookie, played the ten, giving Declarer a free diamond and the overtrick. I grimaced.
Then, I thought for a minute. Actually, throughout the next hand...
It turns out that I made the only defensive error at the table. Do you see why???
Part I is seeing my error (easy). Part II is seeing why my partner's play was dead right.

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