Ian, you're just incorrect in this case. it's that simple. The only comment I'd have is back flattening is not something that should be done with any power sharpening. It's subpar with a worksharp from what I've seen, very subpar from a makita grinder, and subpar from the side of a tormek stone (I have specific experience with the last two).
Fascination with flat bevels instead of hollow grinds is also a lack of experience. You can prefer flat bevels, but they offer no practical advantage over hollow grinds. The rest of the perceived problems with a method that works both fast and plenty fine are just that, perceived...and imagined. You need experience at this point, not more supposition. You're not going to get much agreement from people with the experience you're lacking because your conclusions are wrong. Not as a matter of opinion, either. They are incorrect because they are proven otherwise in practice.