I'm confused, is it part of his job to root for the C's? He's a sports journalist from Milwaukee, who found his way to Boston. I don't think being a Celtics fan is part of the job description.
If I were a journalist in Milwaukee and the Bucks were in the playoffs and the Celts weren't I probably wouldn't say I wan't rooting for the Bucks. I mean who does he want to win? The Heat? The Knicks? Does he have a thing for the Hawks or Bulls?
Again, I can't speak to the specifics without knowing the context, but this is all part of his schtick. Usually when he says he is not rooting for the local team, it will be framed by some statement about that team.
Was he talking about Ray being sent to the bench (other journalists have taken them to task for it)? Was he frustrated with the medical information?
And if it was just that he doesn't want the C's to win, I am fine with that. He grew up rooting against them. I think it is refreshing that a sports talk personality isn't kissing the butts of the local franchises. It makes Felger fun to hate, and more interesting to listen to.