PSA: Mount your own fucking skis.
IMO you can get a much more geometrically perfect mount with a paper mount than any other way. Caveat is I use/make my own templates (check the sth2/warden I posted in the template thread) - which have a bunch of thin lines for the front and rear piece of paper to line up. More lines to line up = higher accuracy in keeping everything centered and lined up. Only way that would result in an off center AT hinge point would be if the boots were messed up. I also always do a 2x4 with a new binding.
I personally feel I'd have a better chance messing it up with the one screw first method. I also take a long time when I use paper templates