Here is a hand from Wednesday. I was sitting East with 12 points. Opponents were silent. My partner opened one diamond in 2^nd seat, one spade by me, two diamonds by partner, three clubs by me, three hearts by partner, three notrump by me, and three passes.

South led the seven of hearts. I played low from dummy and my jack won the trick. I counted my sure tricks: two hearts, five diamonds and two clubs. At trick two I started running the diamonds, hoping that I could set up an overtrick in clubs. That was too lazy.

I forgot to remember an obvious inference for South’s heart holding from trick one. I should have made a mental note that South had to have the king, queen, nine, and perhaps one more in hearts. When I observed South discard the nine of hearts on the last diamond, I must lead the ace of hearts and out a heart to set up my 10 of hearts for a 10^th trick. All the opponents can get is one heart and two spades.

BTW, I recommend that West rebid one notrump at her second turn. The two diamond rebid implies six diamonds.