Mills is very aware of how this does not look like those guys. That's his selling point. Remember, he's all about momentum generation. I don't know if this is a panacea but I'd hesitate to condemn solely because it's not the same as the guys out there now. As for being able to repeat this delivery, I'm not sure why one couldn't. It's quite simple and straight forward (pun intended) and I'd be willing to bet that it's actually quite repeatable.
The big step back is intentional. The idea with it is to have 2 push-offs. One off that back step and another from the posting leg as the hips move past it. Very Marshallesque!!!
If they can solve the problem of loading the hips during that stride, I'd say they have something.
Other than getting the hips loaded, what do you guys find so bad about the mechanics, aside from how the guys out there now don't do it?