Not being funny but if I hit you more than you hit me (and we are talking 7 or 8 times) I am pretty sure I would be able to recognise you??
So, how about, if you attack and the other guy hits you more than "x" amount of times, your stealth is blown?? Just lost a fight after 20 rounds were I hit more than I got hit. I'm pretty sure in a line out I could finger the guy (excuse the pun).
:)