In a game today, I made the mistake of trying to be clever (which I rarely am and never try) and laid a trap for my young opponent.  I was hoping he would play Rd8 and I have mate in two.  (Instead, he played Bxd5 and I went on to win the endgame.)  

This trap had a fatal error that is utterly obvious now, but for some reason I couldn't see it over the board.  I just played Qd3 to "protect" the knight.  Black to move and win.

nice.

I got the answer. 

Ya I wasn't seeing that either. Maybe from the black side I would have though. I'm not used to employing that as a tactic .

Morphy would have been proud.