That's why I love this site! Each and every one of the names I've read thus far have been quality references and hold substance for reasonable debate. Gotta admit though, a young 'n primed Tyson had guys shittin' in thier trunks and probably thinkin' to themselves, "why in the hell did I agree to this"?
I would say Tyson easily and mainly because he had such a mental advantage when you go in the ring against him you thought your life was over when he would bob and weave...a close 2nd would Manny P. that kid is just sufficating!:vonnecunt
Since when were any of those but Frazier pressure fighters? You continue to astonish with your stupidity.
To answer the question, there were certainly guys that applied more pressure than Tyson, as he was actually somewhat of a reserved pressure fighter, one who'd work his way in and pick his shots, at least in his prime. Whereas fighters like Frazier, Armstrong, Pryor, etc would just plow in blasting away. I'd say Armstrong personally, he simply knew no other way to fight.