Thanks for the link. I've never raced and we don't attempt to beat other riders in a descent. This article focuses on the modulation of disc brakes and describes rim brakes as all or nothing. That has not been my experience with rim brakes. Most of them have seemed to me to be able to modulate - but maybe not as well as a disc. I've never thought of rim brakes as binary. The disc brakes on my mountain bike work quite well. I use them much more than I do on a road bike. However, they do tend to make noise after repeated application.

I do appreciate all of the thoughts on this. However, all of this does not answer my original query: If you dump an equivalent amount of energy into a set of disc brakes and a set of rim brakes (until at least one begins to fail), which one fails first and what is the nature of that failure?

I was just wondering out loud. I am too lazy to set up and run this experiment myself.