You’d have to be pretty stupid to think a guy who takes a clean right hand from Dr Steelhammer has a China chin. That shot knocks out most of the heavyweight division. Wilder would be sleeping for a week if that landed.
There's a world of difference between having an unexceptional chin, somewhat vulnerable to a big shot, and being glass jawed.
The injury to G-Man, meticulous match-making & exceptional reflexes helped RJJ secure an ATG spot prior to Tarver and beyond
Roy came to mind and Julian Jackson also came to mind. Roy’s athleticism and speed kept him safe as did Jackson’s power.