Chris,
I read your description of the crash. I would speculate that it had to much elevator combined with being heavy and a rearward CG. The elevator throw is the most critical factor here and many Cap's will snap if the wing's angle of attack is exceeded.

Whenever I hear someone explain that the plane flipped over and they had no control till it crashed I assume this is the cause. Usually they will blame a radio hit because of the seemingly lack of control because they kept pulling up and nothing happened. Actually the wing stays in a stall and does not get a chance to begin flying again. What needs to be done is to neautralize the sticks and add a little throttle, wait a few beats and then slowly pull elevator, hard to do when your plane is heading straight for the ground.

I would guess that this plane only needs 1/2" of elevator throw on low rates, maybe less.