I'm a former partisan of that sort of thinking, so I'm well aware of it -- from the inside, as it were. The trouble with it is that it only works on people who already substantially agree with you. When you're talking to people who don't, at best it does nothing, and at worst it actively impairs your efforts.

Failure to acknowledge this fact is taken as a sign of commitment, I think, in certain quarters, but I've lately come to hold the opinion that such failure evinces a certain basic lack of empathy which augurs ill for the ability of the person so failing to make an argument capable of convincing someone not already in agreement with him.