When you sacrifice anything bigger than a pawn. Do you get a nervous twinge that it might not work? The voice that says that you will lose? Even after you have calculated lines, it doesn't quite seem right. This is a game in which I blundered and came back with an attack.

Nice finishing combo! I'm not that strong a calculator so I have to double or even triple check my calculations before going for a sacrifice.

nice combination. poor white's queen dancing all around the board.

I used to calculate alot, but that turns you off from sacrificing usually. Once you sacrifice alot its not as much about the calculations as it is the positional advantage you acquire from the sac. What having a dominant position does is makes the other person play defense and it is alot harder to play defense than to attack.