What I'm saying is that by using quality as your definition of proof you entire arguement is built on an assumption of human incompetence. By saying "look at this crappy one obviously made by humans, and this good one obviously not made by humans" you're not proving anything about the circles, all you're proving is your own bias. I'm saying that those who claim to be able to hoax crop circles can't fake the phenomena that we have observed. Their BEST effort falls short of what has been seen throughout the world. If they CAN'T do better, there is NO reason to believe that THEY HAVE. Is that clear enough?
But that's all built on the assumption that all the good ones aren't done by the hoaxers. Without that assumption you've got nothing to build this "quality" test on.