Throw-in or show-up squeeze?

Please use next button to play through first few tricks. In view of the diamond gift and tempo, I went after clubs. Lefty chose to continue clubs, but did well to choose the 8 spot, the 10 would have been, for him, a disaster. I won the D return. Then I took a losing spade finesse, and a diamond came back. I rose in order to play a spade up again. The speed with which LHO followed, I felt that this finesse was bound to lose. I know also that RHO has longer hearts from the play. Therefore, a better line than the one I followed might have been: Go up with Spade Ace, cash Club A, exit spade, which RHO has to win. Now he is endplayed and has only hearts to return into the tenace "AQ" in dummy!

At the table, I missed this unnatural line, choosing to finesse again in spades. RHO was out of diamonds and put me back in dummy. I had to execute a precise sequence of moves. I need the H finesse for the second OT, but I can take it in a sexy way, via the show-up squeeze. On the next trick (SA) I keep my D threat card, and pitch one heart, next I play off the CA and a C to my hand squeezing LHO between Kx of hearts and the DQ. He chose to throw the DQ. I cashed my D9 and HA for my last two tricks. The "show up" case occurs when LHO keeps as last two cards DQ master and Stiff HK. When I play the H up, I can see the HK. A 90% board

The ultimate puzzle is why did partner playing a 15-17 open 1C rather than 1NT? Did he fear his D guard? That is not the modern way. Hands where N declared did not get the D lead gift and, on average, took fewer tricks.