This is a brilliantly concise and insightful statement, the idea that by critiquing your side you're scoring points for the other side. It's intuitively obvious in its essence, but this is such a clear and precise delineation (at least to me) of one of the most problematic of our social traits. Based on psychological research findings I've read about, roughly 85% of people believe this unconditionally and 15% see its potential folly. "Silly human race" to quote Jon Anderson of Yes.