I have pretty much followed a variation of his diet since his book Blood and Guts first came out. The main lesson I learned from Dorian's diet is this: you don't need as much protein as you think you do. Chris Aceto also help hammer this message home for me. But the final factor for me was doing bloodwork and watching my BUN. For me, a BUN in the high end of normal means I'm getting too much protein (assuming I am well hydrated and have been). I'm sure there is a large individual variance, but I think most bodybuilders eat way too much protein, at least at the amateur level.
I totally agree with your statement!