There are so much conditions which affect your gameplay ... Sometimes I just don't know if its my mood, my mouse, my ping, luck, or the players against whom I play ;-)
I happen to have ~20ms of ping sometimes, and when that's the case i'm quite efficient with minigun, game also seems to be more "fluid" or maybe it's my imagination. I still have good results when the server is unlagged and got a worse ping (60, 80, or much more), but not as good as with low ping. At this point I can easily make someone fall into space for expl, and it's a way to kill someone who has, let's say 40 of ping may not have (I think it can affect that much, maybe some maps make ping doesn't matter as much as others)
If you can't overcome someone who has a slightly better ping than you, then how could you pretend to be significantly better than him if you had the same and won ? We're not predictable machines. Maybe he had a better mouse than you or you had worse FPS ? Nevermind
Fact is he lost and got frustrated ...