i personally use it for a lot of stuff.. first and most important, some players stay very good even when they're old and i adjust that, it's a personal taste.. another thing i do is use it as sort of a my player, i put my created player into my team (knicks usually), then i create a story in my head like he becomes very good in a few years etc lol.. and also right now i use it for ricky rubio, i created a ricky rubio and edited his stats so he's like a 50-60 range so no one will take him in free agency, but he doesnt suck so much that he'll disappear after the season is over.. then come 2012, i'll edit him to his normal rating (i have him at around 76) and hopefully a team grabs him in free agency then.
