I haven't done it. But to be honest if you have done it once before legit you have nothing to prove by doing it over and over again so feel free to cheese away. However isn't it just more fun and satisfying to do legit? Don't get me wrong I knocked the templar off a few times back in the day, but it always felt like a letdown. I never cheesed atheon though. That cheese looked harder than doing him legit. Your only really cheesing yourself out of a good fight at the end of the day.