A curious hand

We are playing at the table of the best pair in the room when partner deals and opens 2NT.  He is West and I am East:

	♠AJ5 ♥963 ♦KQJT94 ♣3
♠KQ8 ♥KQ2 ♦A5 ♣AQT87		♠T76 ♥AJT75 ♦62 ♣K95
	♠9432 ♥84 ♦873 ♣J642

North passes.  I transfer to hearts and then bid 3NT which partner corrects to 4H.  At this point, North comes to life and, taking advantage of the favorable vulnerability, bids 5D.   The bidding so far:

W

Pard

N

North

E

Me

S

South

2NT¹

Pass

3♦²

Pass

3♥

Pass

3NT

Pass

4♥

5♦

?

(1) 20-21

(2) transfer

What should would you do with the East hand?

I have more than the minimum, so I made a forcing pass.  Partner now doubles and it is decision time.  Do I have enough to pass and pull?   I decided that partner's double suggested that he had only 3 hearts and with the preempt, hearts were likely to break 4-1.  So, I settled for playing 5Dx.  Now, what should I lead?  This is my hand:

♠T76
♥AJT75
♦62
♣K95

At the table, I decided that the auction called for a diamond lead and led the 6 of diamonds that declarer covered with the 8 of diamonds.  Now, declarer had two entries to dummy and he used that to lead towards his spades twice.  That, and the 2-2 fit in diamonds meant he went down only 3 whereas everyone was making 12 tricks in hearts our way for a bottom board.

But note the curious nature of the hand.  If I had led a heart or a club, we come to four tricks. If declarer has to play diamonds, he has only one entry to board.  5Dx down 4 would have been a top for us.

We'd have finished 4 places higher and they'd have fallen four spots lower had I found the club or heart lead.