: If the centre of bouyancy is known, where does the kayaker fit in relation
: it? At the CB, ahead of it or behind it? does the weight of the kayaker
: influence this location? Does sex of the padler have any effect, such as
: different centres of gravity for most males vs. most females? A 180, 180,
: 200, and 220 lb. male and a 120, 140, 160, 180 lb. female would do for
: samples.

My guess would be that the loading of the boat, front and/or rear, would have a vastly greater effect on boat trim than paddler shape, weight and gender. It's a function of the weight of the stuff times the distance from the center of buoyancy - pilots call it "moment arm", and use it when computing weight and balance loadings in aircraft.

For exquisitely fine tuning of the CB, check out Mariner Kayaks. They use a clever system whereby the seat slides back and forth in flanges fastened to the inside of the hull, and the seat is rigidly (but adjustably) fastened to the footpegs, which slide inside a Yakima-style track, so that when the seat moves the pegs move too.