Hood, let me just comment that your dedication to this forum is nothing short of amazing to me. Forums are very expensive, time wise, and you spend a lot of it helping people out. Just wanted to acknowledge.
What I can gather form the photo of the drawbar mechanism looks like something similar to what I had in mind, except that using htdraulic power eliminates the mechanical advantage required for an air cylinder. i.e. no scissors. Hydraulics are arguably more expensive (depends really on what you already have aroud the shop) and certainly a lot heavier mass to move around. On the other hand, it will probably perform for 30 years like the day it was installed, save an new o-ring here or there.
The quill drive is a nice clean deisgn and is also what I envisioned as the way to go for a quill drive. Yours is the first I have seen and it looks to be very beefy. I don't know why, but that's what I expected from Hood . . rugged, non nonsense, bullet proof.
Others have attacked the problem by motorizing the rack, which probably seems logical at first thought.