You don’t NEED to train like a bodybuilder to gain mass, but bodybuilding (i.e. higher rep range around 8-10 and higher volume per workout) is without question a faster, more effecient way for a football player to gain mass. He won’t need all the volume, accessory exercises and single joint exercises, but the higher rep scheme and higher volumes workbest. What would you have him do to gain mass?
And yes, Ben did train like a jumper (plyos and jumps), bodybuilder (higher rep schemes on his bench press and squats) and shotputter (lots of throws and strength work). He didn’t lift Oly’s, but that was Charlie’s choice because of Ben’s less than stellar form. Charlie did like cleans, though.