FBG demo... Real or Fake?

[url=http://www.youtube.com/watch?v=5oJyOHLnfig&feature=related]http://www.youtube.com/watch?v=5oJyOHLnfig&feature=related[/url]

There is a Youtube clip of this song in Demo Form, And they say that its John Deacon who sings the intro?
Is that true?, Or just crap?, And most importantly, IS the demo real?

It's not a demo but a stripped version using the karaoke trick, and the one singing there is Freddie.