Anchorhead said:
He also shot the "there is another" scene in Empire without even knowing himself who the other would be.

The smoking gun, to me, is that Yoda says "there is another" and Obiwan doesn't know it. If the PT reflected George's "vision", then Obiwan knew about Leia and Luke being siblings all along and wouldn't have needed to be informed about this by Yoda. The fact that after Ep.3, he somehow seemed to forget - then remember - about the siblings AND about Vader being Luke's father, means either that George was just forcing it in after the fact, or that Han was right and Obiwan was seriously senile.