Amelia and Francessca - dudes, you totally nailed it. After all haven't we all done this? It is a great story telling song, in the same genre as the songs of Meatloaf and Dio. They try to tell a story. It is something that most people miss when they watch the pod. Every musical segment fits that particular type of music that is called for, and on the way basically gives a quick tour of the history of rock. That is why the music varies through the movie - it starts with the 70's rock of Meatloaf and Dio, then moves up the 80s with Classico, then onwards with the type of music that Tenacious D used to play starting up. Master Exploder is a typical early 90's rock, Break in, and car chase city is typical of later rock.
Keep rocking dudettes.