I believe that most training books or videos have something to offer. You find bits and pieces here and there and put it all together into your own approach. That said, I got a lot out of his book. Is it a great stand-alone reference to use for training a HT or FT dog? Absolutely not. Would it be a good reference for someone training an all-around gundog? I think so.
Like most here, I think the Lardy and Graham stuff is the most useful source of info on training the technical aspect of the retriever games. But I have also read the Dobbs book, the British stuff, Wolters, Tarrant, Goodwin, Gould, and a bunch of others including several non-retriever books. I get something out of it all.
There are lots of great trainers out there that specialize in FTs and HTs but I think if I were a guy looking for somebody to train a good solid gundog, I would probably take a good hard look at Butch. It seems to me that he has a pretty good handle on what most hunters really need in a dog. One man's opinion.
What I really like about Butch's book is the CD that goes with it. The book can be read on your computer via the CD, or you can sit in your chair with the hard copy if you prefer. There are video clips that you can play as needed to help describe things. I thought it was very well done and is full of good information. Great concept!