I knew someone who like to use flat Earthism to illustrate that there's little point in debating someone who has no interest in being persuaded. He'd basically state the Earth is flat and use every rhetorical trick in the book to defend his position, exhaust his opponent, and then say, "Could you imagine how frustrated you'd be if I actually believed any of that?" He eventually got his DDS of all things, but I thought he'd make a good lawyer.