Much of the dialogue was ad-libbed.
In the scene where Derek comes and gets Nigel and David to come hear a song from their past on the radio, the radio announcer's voice is being supplied by Harry Shearer, who played Derek.
When movies are made, scenes are often
left on the cutting room floor.
Sometimes, there will be several versions
of a movie floating about on cable, tv or video etc. Other times, a Director may
release a special cut of the movie.
Early home video versions of the film, which included the mock music video "Hell Hole" and other extras, had a special disclaimer inserted at the very end stating that the band did not actually exist.
There were many deleted scenes for this movie. Most every home video has variants on this footage. Criterion Collection's laserdisc and DVD has an hour of deleted footage, including 15 minutes different from MGM's footage. MGM had different scenes on the VHS and the DVD as well.