Incidentally, the most boring music documentary ever made is the one that came on the bonus DVD to Mr Beast by Mogwai.
And lo, someone has posted it to youtube
Even someone who likes Mogwai cant help but be bored to death.
edit: Im not sure this is the thing that was on the DVD as that was about 45 minutes long, but it was so boring the first time around I cant be bothered to check.