Interesting theory. I know a lot. One has had 1000's off personalities and fragments. Now Jesus told her who her original identity is. She is a survivor, tho still primary personalities exist, all jhave accepted Jesus as their savior and she is uber productive person.
No talk of personalities being a real person in a someone Elese body, subject neve came up.
I would love to talk more on the subject.
DID. Free. Net. Is her website. She is helping others now.