Knives and chisels are just pieces of metal, meant to be used by us, for us. It's no surprise when a blade fails at something it wasn't expected to survive--but it's not as if it were a living being sacrificed in some malevolent scheme. That's not the point at all.
The wonderful thing about such testing is that sometimes we discover something about a blade that works much better than anyone expected--and we'd never know that without pushing blades to their expected threshhold of failure and then beyond.
Cliff's genius, I think, is that he is not only able to uncover such unexpected and wonderful properties in blades--he also has the technical background to then be able to ascertain what it was that gave the blade its special properties. Which means we can learn what made that blade so good, and use that information to make future blades better. In fact, I think Cliff may be on the verge of some work, on indexing properties of blades, that could well have revolutionary implications for the industry.
What I find most surprising is that he takes as much flack as he does, for trying to bring out the very best in our tools and weapons. How can anyone take testing a piece of metal so personally as to become defensive on behalf of the tool? Mind boggling to me. I just don't get it.