Having watched some of his UWF/Mid-South, NWA/WCW and WWF (lol) stuff, I never got the appeal of this guy at all
What was supposed to be special about him, kayfabe or not? His football background? His friendship with mighty talent-relations head/booker JR (NWA/WWF)? His bland-at-best look? His non-gimmick (well except Kabuki I guess)? His lame ass Powerslam finisher? His stiffness hurting guys? His mediocre cliche-ridden interviews? His roid usage/dealing?
I admit I didn't see his Japan work, but his US work doesn't hold up at all imo, besides a few good bouts in WCW (multiman matches like Wargames, couple of good LONG tag matches in the Watts era)
I think you really needed to watch Doc in Japan to get the full benefit from him. That being said, I really liked his UWF run because he was a believable asskicker in that role. To each their own.