This was a nice little game. I played through it as the first guy at least on normal level, and after I got the hang of blocking and counterattacking I could (usually) pin the opponent in the corner and beat the shit out of him, so I say you have every right to respond to people whining "it's too hard" by saying "nah u jus sux, git gud r git lost".
There's definitely room for improvement with, well, pretty much everything from graphics to sound/music and even gameplay (maybe prevent pinning someone in a corner from being so overpowered) but it's still a pretty good game for what it is. On my second playthrough as a different guy the game bugged out and I was stuck crouching and sliding right while the opponent didn't do anything, not sure if that's a bug on my end or in the code (using Chrome on Windows with Flash 27.0.0.187).