See, that's you doing the "tanker" thing by dictating the universal terms of fandom that we all must abide by. I don't hold with that.
In my book, anybody who honestly cares, is emotionally invested, in the big-picture fortunes of the Celtics is a "fan." I think there's ample room for debate about what plans, strategies, and outcomes are best for the big-picture fortunes of the team.
As for the rest of what it means to be a "fan," I think everybody has the prerogative to define what that means for him or her.
If you think making the playoffs this year would be a good thing for the Celtics, that doesn't make you a bad fan, just like believing the opposite doesn't make me a bad fan.
It does mean, however, that we disagree.