There are just way, way, way, way too many stories like this about the guy.Mike Portnoy at a clinic. Spent the first 10 minutes complaining about the gear that didn't show up for the clinic that was supposed to be there (not sure what else he needed, looked like the identical kit that he was using on tour at the time. this was back after the Awake album) then in the middle of the clinic started a bash session on Tommy Lee, Lars Ulrich and a few others. Then tore into Rush bad mouthing them for them not blessing the 2112 project he put together, recorded and finished without any input from Rush then expected them to give praise and their blessing.
After that night didn't care if I ever heard him play again, lost any and all respect I had for him!! Total arrogant, self absorbed clown!