Yeah speed kills ! Its a commonlly known fact in the UK that if your travelling in your motor at 40mph you are 70times more likely to kill a child if you hit it than you are if you hit it at 30mph. True Story
Depends what's behind that speed, sure a brick or car will do more damage the faster it's travelling, but a punch is different, the body-weight, force and technique is what does the damage, not just how fast the punch is travelling. Jabs travel fasterthan haymakers.
Cotto has timing that defeats speed. Cotto has fought fast and slick fighters before and actually does better against them. Cotto's counter jab is his best weapon against somebody like Pac.
Cotto's jab will be the key to any amount of success that he may have against Pac. If he's able to somewhat neutralize Pac's body rhythm with the jab then things could get ugly.