The part I don't get is that the fork angle will have something to do with where the handlebar/front axle alignment lands. That is somewhat if not completely independent of the top tube length. If the forks are very straight, or have some curve will also factor in, won't it?

I'm working through fitting up my new bike (just got it this week) so I can ride a while before a pro fitting (if I can't manage to tweak it in myself). The fork geometry seems to have pulled my axle back, visually. I am comfortable as far as my back and arms on the bike - the saddle certainly doesn't work for me - and I wouldn't want the next size smaller frame, because the frame allows me to stretch out that little bit I don't get on my other bike (a CX bike).