I've been lucky enough to have been the program director at two sports stations.  That's how I know from first hand experience that the WWL's claim that their relationship with leagues does not affect their coverage is utter nonsense. 

In a local market, the teams are aware of what you say. If they don't hear about it from a sensitive player or coach, someone in the office or in sales or someone in the organization listens to you.  And, if you say something they don't like, they have been known to call you and discuss it with you (or with your beat reporter.)  I've had teams threaten to pull credentials on us before.  I've had to negotiate apologies and even, once, send a coach a letter for something we did or face having our access revoked.

As an affiliate, you are a team partner and your take is supposed to be all sunshine and lollipops.  You stray too far and the team lets you know about it.  And it does come up in the contract renegotiations.  In some cases, air-personalities have been fired or banned from facilities because what they said upset a coach or a player.  The myth that athletes and coaches don't listen and don't read local papers is just that, a myth.  Not only do they listen, they listen for what you say about THEM.  To them, it's all about their image

Oh, and if they aren't satisfied with your explanation, they may seek someone higher up the food chain to put the pressure on.  You know, someone in a suit who knows little or nothing about how you run  your station because they are busy dealing with the four music stations in your building and don't really like sports. However, they assume that the team must be right and your morning guy is wrong and we need to back off now because these guys are important.  In other words, treating the team like a client that spends money or something instead of a sports team which is open to public comment and discourse.  After all, what's telling the truth when it could cause us not to be able to get anymore free tickets for clients or jeopardizes the big promotion we are working on between the team and one of our music sister stations.

So, when the WWL says "We have no bias in our coverage", it's crap.  If the Steelers for example wanted the Rothlisberger story spiked, a threat of the WWL being locked out of training camp and having no access to interviews and such would make the WWL think twice about running with it.  As a matter of fact, I think it did.