"Anonymous. You go ahead and argue it out with Richard Gleave. I can give you his number."
Quickstep, there is no question that Gleave's method is a practical way to dance.
The question is, does the figure which it produces move in the directions given for a textbook fallaway reverse and slip pivot?
And the answer is clearly no - it is a different figure. A practical substitute, yes, but as with most substitutes advocated by the rigid body school, a fundamentally different figure. Such are the consequences of refusing to twist your body, in the situations where those who plan to move on the textbook path would need to utilize a twist.
If you draw a line between the commencing foot position and the placement of the first step of a classic or textbook FRSP, every subsequent step will fall on the "wall" side of this line (I am talking about placement, not orientation) On the other hand, if you use Gleave's method, your path will soon have curved across to the other side of that line and your steps will fall to the center side of it.
Given your love of isolated trivia though, I'm going to predict you ignore the substance of this difference in path across the floor and pretend it to be a simple contest of reputations. I invite you to prove me wrong about that, by actually understanding what makes these two different figures.