Not so. I'm reading all this with great interest, but don't feel confident to comment yet. Except that the multiple personality theory seems to contradict VN's positive statements in Strong Opinions about Shade's emotional-spiritual life (doesn't sound like what you would say about one half of a split) and about Kinbote's being a madman who will kill himself shortly after finsihing work on the book. Also, hasn't DN told us that VN denied the single-author theory of "Pale Fire"?

Incidentally, now that I have supplied Dmitri with the evidence he requested, I should be grateful to know his present considered opinion on the putative line 1000 of "Pale Fire".