Fascinating stuff. In my experience not all "arguments" are about getting someone else to understand your POV. In too many cases it was all about making the other person wrong.
That's where it started, and where it will inevitably end. It's an art and science to spot this right out of the gate. Yes, there's a margin of error and you may be walking away from a learning opportunity, but most of the times it's merely stepping away before the punch lands on your face.
Otherwise, I agree wholeheartedly. Calm is in my opinion even more important than brilliant repartee. I've handled some really gnarly situation by not raising my voice and going all Brooklyn on someone. But just listening and talking it out.
Good read!