Liston or Shavers? - Hardest Hitting Heavyweight.

I think if we lined up 10 people like Shavers, Liston, Lyle, Foreman, Marciano et al who MIGHT deliver the hardest punch and measured them with some kind of meter, the winner would be a surprise. Shavers delivered every punch like it was his last one. Liston delivered his hard ones only when he needed them etc. It's fun to speculate on, but we'll never know IMO.