TubeNet

Update: I just received my copy of Visions by Roland Szentpali a couple of days ago. I don't know if this is the reason why Mephisto is never performed, but it's a pretty good guess. And since it was specifically meant to be played on a C tuba BTW. A couple of measures from the ending, Here's an attachment... Is this why?
http://imgur.com/rzKi7oH" target="_blank

He is really, really good. He can pretty much play anything, so things he writes for his own performances are really, really hard. He got to that place one step at a time.