God, calm down man and take a pill! :)

Ozzy is an amazing showman, and vocal-wise, not a very good singer ... not to say that he isn't a great showman, once again, so take deep breaths lol. Vocal lessons from a great coach would help so so much ...his throat would also be in better shape and he wouldn't have to lay out a private pharmacy on his drum set. I've taken theatre; trust me on the lessons. All the great vocalists have them.

And anyway, if Ozzy really knew about voice, he would have canceled; by performing, the guy put his throat at major risk.