I dont think he would have a popular appeal if he didnt have impressiveness first.
Yeah, it's a total package. The drumming would not be as popular if it didn't fit the music, but the drumming itself became something that the band has been popular for. Some stuff is drumming for it's own sake - basically the solos. And there again, what they had was a combination of impressiveness and popular appeal. Most solos that impressive or more impressive aren't things that the average music fan could really get into. Other solos that people could get into aren't as impressive. Or they're just sort of a chops display. Everyone just says "wow, that was really fast and that's cool" but there isn't necessarily all that much interesting going on.