I disagree with the charge that it would shrink the SW universe. The characters were created to be our companions through the story. I think that, when considering how to tell the story before ANH, it makes sense to keep that element in place. It has been said many times around the forum that the Luca$h PT just doesn't feel like SW. I think that is partly due to the poor use of the droids. Sure, it provides a few headaches when trying to retro-fit a PT to SW '77, but it is by no means the only one. And I am a long way from declaring it impossible.