Being untested at something doesn't make it a weakness. It just means you don't know where they stand in that department...
If someone has never been hit hard, do you just assume that they can't take a punch, just because their chin in untested?
I see literally no way Hendo wins this fight. Even if he lands the H-Bomb, people have survived it before (Jake Shields, Shogun in the first fight). There's no telling if he even knocks out Cormier with it. Plus, Cormiers MMA wrestling is far superior. I think he takes Hendo down at will.