Against KilgoreTrout, a 1400 player here. He had a thread running regarding a daft opening system he was enamoured of and with which, so he claimed, he had defeated several players rated much higher than himself. I rose to the challenge and offered to fall into a prepared variation of his, the first few moves being fixed. I screwed it up and thereby confirmed his claim that his opening works. I still think it's a bad opening, but I sure didn't prove it in that game.
PS to GP, yeah, go ahead and search the archive for that ludicrous game, publish it for all to see and have a good laugh. Cringe cringe. We all make blunders. I console myself that even Capablanca once dropped a piece in the opening against Tarrasch.