Originally Posted by niznai

Why do you care if it's vertical or not? The point is to move the rack symmetrically, and when it's vertical it doesn't.

Either way, Futabas have 23 splines or 25? - either way, an odd number which means horns are bound to be centered to one side and off centre to the other side. I would hazard a guess this is by design, to create a finer adjustment when positioning the horn in situations where you can have it either way.