"Where'd you get that fact - wikipedia? - in that case, I'm allowed to ignore your argument. I get my facts from talk radio."

That sounds like a perfect example of how knowing about biases can hurt people. It's similar to something I often see in religious arguments: someone who wants to rationalize away an argument will often come up with a really flimsy counter-argument, overlook its flaws, and stop thinking about the issue immediately. It's a particularly pathological case of being more critical of opposing views than ones you agree with.