I noticed for the first time tonight. During the sequence near the beginning, a drunk Norman Maine joins Judy and the guys on stage. She steps toward him and her lips are not moving but her voice is continuing to sing along.
share
This is so blantantly obvious, that it has been deduced over the decades
that this - along with some really jarring editing - were done deliberately
by Cukor, to show the ultra thin line between Hollywood phoniness and
blurred, Hollywood reality. Keep in mind that when Garland is NOT
lip-synching and approaching Norman, it is HIS drunken point-of-view.
The odd editing jumps include Esther's drive home with Norman, as well
as their kiss in the doorway of their motel room on their wedding night.
I agree that it is jarring and unnerving...but, in its own way, oddly
effective.