Kentucky-Florida 4 second call?? (Video)

[Nevadaref]

I don't understand how the slight movement of the left foot aided the player in his pump fake. It's not as if he took a large step to a new location or went two feet into the air. His foot perhaps came an inch off the floor.

I don't think that this foot movement had a major influence on the upper body movement or the player bracing for the impending contact.

I certainly don't see this slight foot movement as something that I'd come 45 feet to get in front of my partner who has a clear and open look at the action.