The answer is the Celts could improve and still miss the playoffs. If Miami gets back Bosh, there's a team that could knock Boston to the eighth spot. Then it's just a matter of losing one or two more games to teams like New York, Detroit and Orlando who should all be at least a little better than last season.
To me, optimism and realism aren't mutually exclusive. I'm optimistic that the team will play with the same spirit and Stevens will get the players to buy in to a system where they're not going to get the minutes they might normally get. But I'm also realistic that it is very hard for young teams to win in the NBA and it's almost certain that Ainge is going to make at least one semi-huge move. There's just no way that ET, Lee and Amir are all going to be on the roster after next season.
But thinking this team is a lock to win 50 games is stretching optimism almost to the breaking point, while thinking this team is going to win 25 games is about as realistic as my chances with Jennifer Garner.
Mike