Just to refresh my memory, I watched a video to make sure. Doesn't look like they got knocked down to me.
http://www.youtube.com/watch?feature=player_detailpage&v=WXhZ3GQTgSM#t=533s

I'm going to take a guess and say that H2H took down health as well as fatigue in Oblivion. If the health was lower than the fatigue, then the character would die before they were knocked down.

nope. but if a modder or bethesda can add brass knuckle type weapon it will.
as far as vanilla goes though it just tells you you must have a weapon drawn.

No... Read my last two posts...

Okay, so I was slightly wrong. But I was right in H2H doing both health and fatigue damage, and the video I posted proves that.

Anyway, it doesn't matter. I do not wish to derail this topic any further, so let's say no more on this.

Not very viable, unless you play a Khajiit and exploit the [censored] out of Enchanting. Then it's viable.

If you play in PC you can easily use console and write "player.setav unarmeddamage 50". 50 - 100 i dont recommend much more. Default is 4 for to rest exept khajiit and argonians.

Damn cheater