Redbadge
Explorer
I haven't read the whole thread, so I don't know who used 'meat' first. But you may be taking it much more literally than intended.
I've never heard of anyone who imagines that high level PCs actually have denser bodies than they had ten levels ago. What I have heard, and this is my own preferred philosophy, is that PCs get [more] magical as they gain levels. D&D is a magical world, so it follows that even its most mundane denizens don't follow all of the rules we're accustomed to.
Namely, all D&D creatures have a certain amount of magic body mojo that protects and heals. And the more it's used, the better it works. And that's why the 1st level PC loses his head to the dragon, while the 10th level PC gets a hickey.
Still, that isn't what the OP suggested. He suggested HP as just "physical damage", not as increasing magical mojo, which is something I could get behind under the right scenarios.