I agree it would be nice to have a clearer picture of what anti-PC folks think of themselves as being against (and what pro-PC folk think of themselves as being

I agree it would be nice to have a clearer picture of what anti-PC folks think of themselves as being against (and what pro-PC folk think of themselves as being for). However, it's also useful to know people's feelings towards a phrase _without_ defining it, to understand what they feel about the term as _they_ interpret it. This gives a sense of the political atmosphere surrounding a term, which can be just as important as what the term actually means. This isn't how things would work in some "ideal", perfectly rational world; but that's politics for you.