That's easy to see. Tiger didn't win every tournament last year and look how he's playing as a professional. Some of those players who beat him are still around including Aaron Oberholser from San Jose State, who beat Tiger on ESPN last year in the U.S. Collegiate at Pasatiempo. College golfers hit average and below-average shots, just like the rest of us. I know this seems to contradict my first point, but it is easier to see your own mental and physical struggles in the games of collegiate athletes than in those of the pros.
Seasoned professionals are mentally tough, sometimes to the point of stoicism.
College players are more apt to wear their emotions on their sleeves, allowing you to watch them grind mentally as well as physically. They dress for the weather. If it's hot they wear shorts. If it's cold they wear sweaters. I like it when it's cold and players still wear shorts.