I've pulled a 100lb bow, though this was very long and thus smooth. A heavy and long bow is easier than you may think to pull if it doesn't stack. I tried to pull a whip tillered 120lb bow and that just reached a wall at about 20 inches as the weight really built up steeply over that last bit of pull.
I made a 100lb bow but I found this quite difficult to pull until reduced to 90lb so it bent more in the handle and less at the tips. This made a suprising difference as the weight was more progressive.
Pulling a heavy bow is more about technique than anything I think. Guys are pulling bows three times the average draw weight, but they aren't three times as big! Yesterday I watched a guy pull a 170lb bow, anchor, hold for at least a second and then loose.
Personally I think that most fairy fit men could learn to shoot a 90 to 100lb bow without too much strain if they get "into" the bow instead of using arm muscles. Technique and leverage is what it is about. "Proper" target archery methods are about the worst place to start as these do a fair amount of damage to the shoulder joint with 35lb bows!
Mark in England