It has nothing to do with Floyd and if you think speed is the only and most important factor,you really need to watch some more fights son! If that was the case,Zab would have walked ALL OVER KT,as Tszyu was not fast at all and did not even throw combos!
Zab's advantages are speed
Tonysower,volume of punches,chin,can cut of the ring,and if Zab thinks Floyd hits hard to the body,wait until he feels Margarito etc etc.