If excessive weight is on the hands and wrists while riding, is it correct to assume that (excluding other issues of fit) moving the seat BACK on the bike will produce less weight on the hands?
Looking at it one way, it seems that having the center of body mass behind the support (the seat post) would better balance the rider on the bike thus placing less pressure on the wrists.
Looking at it another way, it seems that having greater distance between the rump and the hands would (of necessity) put more pressure from the weight of the upper body on the wrists!
I suspect the the first take is more correct because (despite the fact that the bars & seat can be moved in relation to each other) the fixed point of bike contact (and the only immovable one) is the pedals.
I've read several online papers on fit, but the ones I've read focus more on power transfer and don't give clear explanations of how position affects wrist pressure.
Finally, if my first hypothesis is correct, it seems to me that most bikes have insufficient seat tube rake to minimize wrist pressure (a function of the "racing" angles that are prevalent in design these days?). It also seems to me that seat posts with variable set-back would be extremely helpful, though I find no such designs on the market.