this is all bs guessing but:
(this is all flat ground cruising on the hoods. It'll change when on a curvy descent in the drops)
not much on the hands. If there's too much there, it's a problem. Maybe 5-10%
while pedaling I'm probably putting 25-35% on a leg at a time (maybe 1-2% being pushed around by the other leg when on the backstroke), although when hammering it's more like 60%
that leaves 55-70% on my butt.
anyone want to refine my numbers?