Stop the personal attacks, god damn.
Back pedaling, to my aware-ness, gives a -50% speed... So unless it's a naked guy with 10 athletics verus a man in black armor with 0 the guy will be able to do just fine.
I personally use my speedy character as a rogue of sorts, flanking around the group and hitting them from behind as my allies fight from the front. The speed increase is noticeable, yes, but it's not all that significant. You'll pull ahead of the initial rush out into the battle field and you'll probably out run someone chasing you, but you won't be fast, you'll just be slightly faster then everyone else.