I saw this a while ago. I think it's a very clever and entertaining video, despite the very forgettable song.
Isn't it obvious that the 'exposure/rehearsal' video was released to increase the interest in the song and artist, helping the (albeit limited) viral aspect of the thing? We are discussing it here, and it's been on at least two other fora in the past few months. I doubt it would have blipped on our collective radars if it were simply released as a one off video.
I think the most amusing thing is the very start, when the clapperboard operator says 'Take 57'.
As for the projector in the rehearsal clip, it's not even on during the take...
Take care, Ian