Tuesday Morning Quarterback, an awesome column that used to be on ESPN page 2 and now NFL.com, did a good commentary once on rookie holdouts. He basically said that agents are at fault for concentrating too much on the short term, trying to help themselves (by getting a huge contract, they get a cut of everything obviously) more than the player. A rookie who signs early gets a lot more practice and can be integrated into the system a lot easier and earlier, allowing him to perform better for a longer period of time and earn more money the next time his contract is up.