I was looking at Paralyzing Strike, which requiries the execution of a backwards
power attack. How effective could this be? If Im running backwards faster than
my opponent, the attack is going to miss anyhow.

Maybe Im missing something, but seems kinda silly to have to backpedal to
activate a move.

I don't think you can backpedal as fast as an opponent can charge though.

I don;t think you are running backwards, just that you pull back as you execute the power attack.

Perhaps, still sounds like you have to be moving backwards,
otherwise you would be standing still and it would register as a normal
standing power attack.

/scratch head.

It is much easier to pull of with a 2hander. Since the reach is longer the timing does not have to be as precise.

It is harder to do, but can be done with practice. In oblivion where your character moves at 10 meters per second, It can still be done. The trick is to starting a standing power attack and pull back just as you are about to execute.