amaterasu useless vs tobi

[OG9TAILS]

My theory is how do you know when it's really Tobi you're speaking to, He has plenty of zetsus that can become anyone and duplicate their chakra. It's the same as Kakashi using clones to start his fights, I mean why not have fakes do your bidding while you stay safe in the background. Just a theory. But if you want to use evidence of how he could survive, I'd use Juraiya's example he sealed amaterasu away to protect the frogs belly when Itachi escaped, who's to say Tobi doesn't have a similar seal if not better.