Basically, whoever put these videos together takes performance clips of bands/people...such as Santana, Eric Clapton, KISS, Slipknot, Creed, Eddie Van Halen, and others and overdubs the music in such a way that the noises you hear actually fit with the motions of the band, but it obviously isn't them playing. it's pretty funny/stupid/random but a decent waste of time for a couple minutes.
The Metallica version actually sounds like some lame high school cover version....
of course, this wouldn't be complete without some...
yes, i know most of these get annoying quickly, but if you
can brave it and listen to them, they're marginally
entertaining for a few minutes. at least i thought so.
some people have a lot of free time on their hands.....