I tend to go the opposite with that one. I'd trust coaches when talking about football strategy but not when voting, hell most of them don't even watch the games of the teams they're voting on because they're coaching their own. I wouldn't really equate that to being in the trenches. There's no doubt they are trying to jockey for position in polls to help their own cause and their conference's cause. Coaches use polls as another strategy to their gameplans. It helps their strength of schedule which in turn helps their BCS standings, it helps motivate their teams, and it helps the overall appearance of their conferences.
Of course you use it to your advantage. You'd be a freaking moron if you didn't. Writers are about as objective as Fox news. In other words they're not.
As far as equating it to being in the trenches I have no problem equating it to that. I'm going to assume you mean don't use a war reference in sports.