Leeneia - I'm not so sure: he's using a lot of unconventional technique - fists, knuckles, rolling to the side of his hand, possibly striking keys with two fingers at times, splayed stiff fingers (not to mention the elbow strike!) - and at a couple of points you can see the stress in his hands as he pounds the keys. Notice how big those hands are, too. Also, notice that he is playing mainly the black keys, which probably allows him to apply more force than he could manage with the white keys.