Maybe a good athlete with some potential. Maybe a guy with no chance to play. The latter two are more likely than Brooks being the next Gonzales.
Assuming he can learn the basics - running routes properly, evading press coverage, etc, who knows how he'll react to the hits he'll have to take. The guy hasn't played football in a long time, and the hits he'll take at this level are nothing like the hits he had to absorb years ago.
Keep in mind that Brooks still has a year of basketball eligibility left, and he'll have his degree. He is not a Big East/Big Ten caliber basketball player, but he can start at a low level Division 1 program. A fun year playing basketball at that level while taking the minimum load of grad school classes will have some appeal. He might decide that basketball is the way to go after a week of football practice.