Is there a secret to hand-to-hand combat in the Bourne Conspiracy?

I've played the demo and think the game is fun and worth buying, except I SUCK at the fist fighting. I don't mean to sound conceded, but in any other game with melee combat I do relatively OK. Is there something different about fighting in this game? When I press the ons, the game character doesn't respond, doesn't respond right away, or doesn't respond the way he should. For example, I try to chain the square and triangle ons for varying my attacks, but I still use the same combo and sometimes Bourne just doesn't throw the punch when I press the on. He doesn't react every time I block and the triangle attacks never work well. The on doesn't even work when I try to chain it in with the square attacks, and it delays way too much when I try to use it alone. I feel like the game character isn't reacting to the commands I put into the controller. It's just frustrating and anyone that owns the game and has an answer, please help. And if you're just going to tell me I'm just bad, please don't bother. If you have the same issue, please let me know so I feel less frustrated. Thanks.