HE is very long limbed, even when he gains weight, it wont look like he has gained what he has. Seems to be very low body fat.
If he gains 25-30 lbs in 4 years, he is going to be a damn beast with his speed and pop.
Can't wait!!
EDIT: Forgot to add that he seems like a great kid and smart enough to graduate early and enroll early. Good things to come for this young man. Hard work always pays off.