... as far as it goes. It goes as far as a kind of Peter Jackson Gollum -- a half-baked notion of psychological complexity.
What it doesn't explain is why "Don Trump" should exist at all. If you're going to posit this level of rational self-interest, then you should take it back one step: Why even run for president in the first place? Why put yourself in a position where The Donald needs to create The Don?
My take: Trump never intended to become president, but he did want to transform himself into a sui generis reality star. That's why he wanted to win more than the public's eyeballs. He wanted to win their votes. That alone puts him in a category-redefining place among reality TV celebrities. Snooki can't compete with that. Rush and Sean and Kim and even Howard can't compete with that. He'll wind up the new King of All Media, with a reality TV-cum-radio-cum-web-cum streaming empire of which he is the impresario, host and star. People will tune in every day just to see what outrageous thing he'll say next. He'll give a show to every tinfoil hat conspiracy theorist in America. He'll claim that he speaks for the real America -- and would have been president but for the politically correct Establishment. He'll continue to generate controversy after controversy -- including, I expect, some legal ones. I think this reality TV empire will have a very active version of Court TV (or, I guess, Judge Judy-cum-Jerry Springer). He'll file lawsuit after lawsuit -- welcoming the malicious prosecution counterclaims. Maybe he'll even have a Malicious Prosecution Watch show. And he'll sit amidst it all with undisguised glee.
Donald Trump has been transitioning for two decades from the scion of a real estate empire, where he hasn't done very well, and where his natural talents don't seem to lie (even if lying does remain a natural talent). He's basically pursued two paths over that period: 1) the wildly litigious general counsel of a real estate equivalent of a patent troll, and 2) celebrity clown. The latter has looked increasingly more promising over the years -- but maybe he doesn't even have to choose.
In that context, one doesn't need to ask why The Donald created The Don. It's the obvious business model.