.....What if the Doctor was reborn, and perhaps doesn't even remember his earlier incarnations himself - except when his mental barriers were broken open during the mind-wrestling contest.
[The Doctor watches his original self on the laptop screen
Howdy, stranger! This is Hauser. If things have gone wrong, I'm talking to myself and you don't have a wet towel around your head. Now, whatever your name is, get ready for the big surprise. You are not you, you're me.