Piano Playing
For a movie that centered so much on piano music, the playing sounded oddly thin - rarely if ever did it sound like two pianos.
There was at least one shot of Jeff's playing wherein you could tell that he learned enough to "finger-synch" along with whoever did the real recording, but it wasn't 100% on and you had the sense they included that shot to say, "See - it's really him playing - isn't that realistic?" And they answer is a luke-warm "sort of." Probably not worth the effort for so-so results.
Do you know that guy?
No. But he's a dick.