In the documentary "Pumping Iron" he manipulates an entire family, who trusted him as a friend. Oh, and he also boasts about this in front of the camera.

I would consider his autobiography to be a brilliant marketing piece (with the positive and negative connotations of the "marketing" concept), although of course this is personal opinion, and I doubt this will be ever fact-checked to dis/prove it.

edit: of course, I don't imply he is devoid of good/inspiring traits.