I think one from most Tyson's advantages in career period until 1988 th and Rooney & co gone were also his legs. Despite he was small HW, even then his legs were more agile and flexible than modern CW guy's legs in their prime. His style was with heavy usage of height and angles change with legs. Also a lot of his punching was impressively powered by good leg work. To add to this his athleticism and huge power for his weight and size + being small target this was something unique. Legs for HW I think prime Ali in 60 ies had the best ever and after this: prime Tyson till end of 1988 th.