I agree. The GP post describes the HS policy league I participated in fairly well, except that we didn't have parent judges. We were a small, county league in a league that had all of 4 or 5 schools participating, so we were able to get by using coaches as judges.

And, lest you ask the question, no, the coaches were not overtly biased toward their own teams. My partner and I definitely beat a few teams in front of their own coach as the judge, and we definitely lost a few rounds with our own coach judging. There were no explicit position statements by any judges, either. They only rule was that the affirmative must advocate for the plan in order to win topicality.