The myths surrounding Zeppelin include the oft-told tale that they sold their souls for success, as proven by the death of John Bonham, the death of Robert Plant's five-year-old son from an undiagnosed infection, and Plant's almost-fatal car accident in Greece.
These tales start, and grow, because they add to the mystique of the world's biggest rock band, and they have been around since the days of Delta Blues legend Robert Johnson, who was supposed to have sold his soul for the ability to play guitar.
Judas Priest were famously sued for 'backwards messaging' - the case was thrown out when exhaustive analysis showed that one 'word' was actually a breath sound, and another song referred in its 'message', to eating chewing gum.
It's nonsense, always was, always will be.