I really don't think that losing Losman and/or Evan affects free agents.
As you can see Buffalo has signed quite a few of the top FA the past 2 years.
If the Bills started losing top notch players that might be different.
Evans is a better than average receiver , that's a fair assessment.
And Losman is pretty much a bust.
These aren't the type of players that make big news with free agents league wide.
Besides the main factor in free agency is MONEY not Lee Evans' or JP Losman's mouth.
Beyond that I am not aware of the Bills "jerking players around".
I think you have a very vivid imagination.