Why would shutter-priority be a pain? You still can steer the aperture by setting the apt shutter-speed. (The AE-1 will show the corrresponding aperture in the viewfinder, though not the set exposure time.)
The idea behind shutter-priority auto-exposure was that shutter-speed is of more effect on a photograph giving a sharp image (of the scene in focus) than aperture-priority.
That more SLR's offered aperture-priority was based on the greater technical simplicity of it.
Last edited by AgX; 02-20-2013 at 08:24 PM. Click to view previous post history.