It's very important to have a feel for the limits of a tool, which requires careful "listening" to it while in use. If you're in tune with it enough you'll know exactly how far it wants to be pushed without damage. That's just as much an acquired skill as sharpening is, though, and takes practice. Some folks instinctually "get it" and others have to put a lot of effort into getting the knack for it.
I agree, but sometimes mistakes are made and knives break. Maybe when you're hungry or fatigued. At those times, I'd like to have a knife that is over-built.
How much over-built... 10%, 37.5%, 100%? I suppose that's the more interesting question. :yawn:
Maybe a knife that's too over-built will cause you to become fatigued earlier... hmmm...