The quality control coach typically breaks down a lot of film, they typically do a lot of the technical stuff that all the other coaches don't have the time to do. I know l somewhat do it at the high school level typically taking care of Hudl, and scripting the other teams offenses and defenses. A lot of the programs that assist in breaking down film have room for error. So somebody needs to go through the film and help script the opposing teams alignments, formations, tendencies, ect.ect. It's honestly one of the best ways to learn the game, but damn it's a grind at the high school level so I could imagine in the pros. But sign me up haha