I have a dog that whos daddy was a duckhill dog. The genetics seem great, I've used milners methods to train, to an extent. I've incorporated a few others here and there. I do firmly agree that the complete positive reinforcement method he preaches is easier for the trainer, when you look at the psychology of the dog most of his stuff makes complete sense. I've purchased his videos and watch his forum on a regular basis, I will say that he comes across as condescending. The man seems to know his stuff, and I have a 10 month old pup who is very disciplined that I trained with no prior experience following his methods. If you do not intend to run trials ect... Then I would say his training methods are great, he's more of a hunting mans dog trainer these days.
I have only seen one true duckhill dog and he was good, my pup has duckhill bloodline and is calmer than your typical lab, had majority good traits that you would ask in a dog.
I know now this isnt a critical article and I have never delt with the man personally but this has been my experience.
No BS