You don't keep the same team though. Players retire and you have to pick new ones. Unless you can save up a ton of cards that boost your player to 99, I doubt this will happen. Not saying you won't have a stacked team, but you will need to replace players in the game. Plus as it looks, certain players react better to boost. Are you going to spend points boosting Crosby's shot power, or are you going to put it on Hall? And with seasons last the month then playoffs, I doubt you'll see total 99 teams.
I just hope when a player "retires" from your team that he isn't gone for the entire game of NHL11 but rather just that season.