You see the SNL version from 1992? John quit the band moments before going on stage, then had to be talked back into the band so they could perform. So, he decides to go back on stage, but intentionally changes the intro to make it sound bad. He ended up leaving the band for six years later that year, while on a Japanese tour.
You can catch that here:
http://youtube.com/watch?v=Tm_j4_JmREo&mode=related&search=And you can see the other performance the band did in the same episode, of Stone Cold Bush,
HERE which is just full of bad tension... And Anthony accidentally knocks John in the eye with a microphone, which is fucking hilarious