The Three Stations by definition are Address, Top and Finish. End is just some extra gravy on the potatoes for those who like it.
When I was at the practice tee of the 2008 Masters I was really struck by how many of the pros stopped at Top for an Iron shot. They went to End with the drivers maybe. I think most amateurs take it too far back for an iron shot, even a long iron. You really dont need that extra travel up there. It gives you a little Delivery Path Hand "arc" up there between Top and End too as the hands go past the point where they can travel a relatively straight line to the aiming point.
Combining the advantages of stopping at Top with Homers advice to sustain the rate of acceleration with steady, smooth acceleration makes G.O.L.F. much more manageable, consistent and easy. And not at the expense of power either given a small pulley wheel. Weird but wonderful, again.
Ok, but what I was getting at is that maybe Single wrist action cannot travel to end? If you try, maybe it gets bent out of shape or something??