From what I can recall, in at least the last year apart from for "simplification" from an already won position I can't remember (intentionally) sacrificing any material, piece or pawn which didn't lead after working it out to the re-gain of that material or mate. Perhaps that says a lot about my game. 
Before a year ago it wasn't that rare...
Dirty Chess Secrets.
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I know. I think I could get through that unscathed, which is probably why I've never learned it. But I should probably know the actual line a few more moves deep.