Bingowings said:

I did suggest earlier that Darth Vader was a bit like Dread Pirate Roberts in The Princess Bride.

A title that was passed down from one masked warlord to another to create the impression of an invincible leader.

Seeing as Vader wears a mask in the OT, Maul has tattoos in TPM and Grievous is a mostly robotic cyborg in ROTS you could in a rebub call them all Darth Vader to cover Anakin's real identity up until ESB but it all falls down to the duel with Obi-Wan again.

It's THE major stumbling block to preserving the mystery (far more than the "former pupil of mine" line in ANH)

I wonder what Ady has got up his sleeve. He isn't giving any hints!!!