Rundgren may sometimes appear to be a bit self-absorbed, but he has a lot to offer in this retrospective documentary. He describes some of his early work, and explains why he largely worked on his own (he finds that few musicians have the high degree of patience that he demands).
The musical content is (mostly) superb, and there's some live concert footage included. He explains his somewhat unique way of working, and comments on some of the music from other musicians that he's worked on - sometimes as a recording engineer, a musician and often as a producer.
The range of his work as a producer is also mentioned - he worked with bands as diverse as Sparks, Meatloaf and The Tubes.
Definately well worth watching if you "get" Rundgren (many people don't!)