Age and league is pretty fundamental to how I project a prospect's progress, but only in the context of their performance. Age does serve as a proxy for having a complete scouting report on a guy, though. I'm letting them do my homework for me, if I say a guy has a chance to be a star. "He's in Ft Myers at age 20? Guess the team thinks a lot of him. Could be in the majors in a couple of years. That other guy there, he's 25; even though he's hitting better, it could be hard for him to get a cup of coffee." Ya think? Number of years of pro experience also matters. I'm more lenient waiting for a struggling 24 year old who came out of college than if he was signed as a free agent from the Dominican Republic at 16. And outliers like Colabello, who didn't face tough competition in his early twenties, throws off such gauges as well. I was once 20 years old, and it wouldn't have done a team's prospect list any good to put me at AAA.