When a sword strike hits so well that it comes out the butt, that seems like a natural 20 on a 20 sided dice right there. XD Maybe if you get a 95 to 100 you should get a critical hit that kills her right there.

I can see the handicap system used when there's a good excuse why they could hit or miss, but generally my character wouldn't be failing all that much as she's not pushing her limits at all in the fight. An olympic weightlifter wouldn't have to roll a dice to lift a 20 pound weight, after all.