Another idea that popped in my mind. What if Al's doing some kind of parody medley? One piece would be "Don't Download This Song" and the other piece a song about girls, and maybe another piece a song about cats, and so on. That would explain the different animators. Each one could be animating a different song in the video.
why would he do that, i would seem like Al has ADD or something and can't keep his mind focused on just one topic
switching topics would destroy the song