This would exclude people like Zhang 3 Fung since he created Taiji and Wudang arts with a foundation on 9 Yang. I'm trying to think of a an exception to the deterioation of martial arts in later eras, as someone who created entirely his own martial arts from scratch (preferably with a solitary life also) should be able to do it in any era. I'm not sure if Huang Yaoshi counts as I don't know if he had any outside influence, but he generally created and mastered his own arts by himself. He hadn't fought the other Greats for like 20 years after the first tournament and he still improved greatly. Same with OYF. I wonder if they would have reached anywhere close to their peak if they were born in the DOMD or Flying Fox era.