We had this Fight! where one character, a knight, squared off with his nemesis in a tower and it was all very dramatic and awesome, and to give the other members of the party something to do, the GM had a couple mooky men at arms in the room, too. Well one of the characters had been built as, like, an Olympic knife fighter with B6 Knife and freaky high reflexes. B5, I think. Don’t think about it too much.
Anyway, the knife fighter wins the positioning, gets inside, and starts landing superb hits on this poor man at arms on after another. The guy is dressed in heavy chain, I think, from head to toe, so the knife just skips right off, and in roll after roll the GM is not rolling any 1s on the armor roll, so the armor isn’t even coming apart. The knife fighter’s player gets really annoyed because he feels like he ought to be able to strike at the man’s face (his character is moving every hit to the head) but the system makes no provision for it. He can’t even declare a great strike because the knife is one-handed. Eventually the knight defeats his nemesis and the man at arms surrenders to the frustrated knife fighter.
TL ; DR What do you think about a rule that allows characters to spend attack successes from melee attacks to increase the VA of their strike, reflecting strikes at less-armored areas on their opponents? Stabbing your opponent in the face rather than the side of his helmet?