I think if you were to get efficient at that technique you would be surprised how well it works. He may start off there teaching down ( I don't know if he does or doesn't) at a distance but it doesn't end there,
There are some good things about the video I would apply. Timing of his yes and good response might capture dogs attention. And I assume you don't need to treat with food for his system to work.
Was not sure I like the idea of when he tells his dog down way out, then lets the dog know he is right, the reward yes and the dog runs in to get the treat? That is not a good application.
If I whistle sit my dog way out on a blind and he sits promptly and I say yes or good which is what I do b/c it signals to him you were good sitting not to come running in! So I was interested how you would stop that from occurring. I am always thinking how is that going to help me attain my goals with my dog in what ever venue I enter. It has to be applicable and doable, easy and acceptable for my dog.
IMHO some pups need a little more than treats. No offence to Ellis, he did speak about that firmness on the video. Need to see more on that subject, other problematic behaviors and more info on his methods! Very interesting video, however.