Leia, do you remember your mother? Your real mother?
Just a little bit. She died when I was very young.
Talk about burying the lede, Leia. JFC.
If GL hadn't sold, there would eventually have been a superduperhyperspecial edition that would have changed that line, among others, because he obviously didn't mean it literally and it wasn't his actual vision and only 1980s technical limitations forced him into permitting scripted lines that turned out to be bullshit. :-)
That detail wasn't in any of the movies so the line in ep 6 still makes sense the way you thought. I'm pretty sure anyone would assume that's what she meant, since we never hear that she knew she was adopted. Whoever made Bail's wife die in the explosion of Alderaan is the one who messed up, or Lucas ignored that addition when making episode I.
At one point, Lucas admits to going back in to post-production and drastically recutting the movie to fit a more kid-friendly Disney-esque media market. Specifically, he was very excited to give Jar Jar Binks a bigger role. I'm convinced there's actually an excellent film laying somewhere on the cutting room floor and Lucas's own vanity was what stole it from us.
Also incidentally, the original New Hope screenplay was a total wreck. His first wife had to completely recut it before shooting began. She became good friends with Carrie Fisher, and Fisher learned the trade of script-doctoring from her masterfully. They both went on to work behind the scenes in a number of popular movies (Fisher even has a cameo in the first Austin Powers, where she tells Austin to quit all the silliness and get to the plot). There's a good reason to believe that Marcia Lou Lucas was the hidden hand that made Star Wars a hit.
That theory missed something that jumped my synapses right at the end. Palpatine killed Vader in order to revive. He pulled the same fucking trick, his love of Vader and his hatred at his betrayal mixed right at the end, and he used it to hitch a ride to his clone stock. Man, fuck, that just ruined the sequels all over again.