It's a credit to Cus obviously, but it's due to his system peek a boo/dempsy roll, when he dodges a punch the opponent is extended out, and Tyson is now in great position since he is already in a wind up ready to explode on the unsuspecting fool.
If you watch the 1st video they discuss how Cus devised a system to counter when your opponent misses..Excellent stragedy.