You're putting waaay too much thought into this. Nothing with with keeping function in his routine especially if this is the way he warms up (I'm assuming he's doing this before he weight trains) beats the hell out warming up on a bike or treadmill. I also have to assume his S&C coaches throughout his college and pro career instilled in him proper training and warmup protocols. You still want to train to keep injuries down.
Im a cert CSCS
he has proprioreceptors that are accustomed to that type of training but sport specific training and specificity come into play now
to COMPETE at national level bb'ing is ALOT diff traing than football - one is pure hypertrophy and manipulating energy pathways thru diet - burn more bf thru low-mid intensity cardio, the other is power, speed and agility -- that relyes on the ATP phosphagen system and some glycolitic response
if this guys warms up with these exercise its still burns up his glycogen stores that he needs to push out reps needed for progressive overload to stimulate more muscle mypertrophy - not more plyometrics and agilty speed drills - that part of training is actually reserved for reseason and in season football players cause you train at 75-85% vo2 max which his body starts to use the oxidative systems more
he needs to not burn up so much glycogen - cool, do some plyo and box jumps once a week to stay fit but if he's going to be a champion level bb'er those training protocols area ll wrong - his energy pathways are going to get outta wack and he gonna burn out quickly when he needs those last few reps....plus his type ! muscle fibers are responsible for his performance when he's using oxidative pathways -- if he trained heavy and hard he can can his type IIx into type IIa whic reqiure less oxygen thus his energy enzyme activity wont we so taxed and he had time to recoperate and train heavier next time around
