At some point I was working for a shop that did smartcard-based payment systems. I was patching some smaller bug when I noticed a call that was suspiciously clo

At some point I was working for a shop that did smartcard-based payment systems. I was patching some smaller bug when I noticed a call that was suspiciously close to an assert() that was accidentally left in. Merely commenting it out made the payment handshake complete 50% faster. Being an eager junior as I was I went to the principal dude who wrote this part (and pretty much the rest of the core) and he dismissed me with exactly that - that's impossible. I decided to push it a bit and went to PM with my demo, he was equally awed and summoned the dude... to which the dude said, and I'm paraphrasing to soften, "this fucking bonehead just commented out the RSA sig verification for the handshake." That is, sometimes the claimed "impossible" is indeed just that and the speed of response comes from the experience rather than ignorance or arrogance.