: 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.

That was clear as mud, so here goes another stab at it. A 200 lb. weight located 1 inch from the center of mass has the same effect on trim (bow-up or bow-down) as a 20 lb. weight 10 inches away, or 2 lbs. 100 inches away. Ergo large loading variations in the cockpit have little effect on trim, although they will affect how high the boat rides in the water.