I hope you are right too. I don’t like the theory either.
I just do think that Colin thought they were two separate human persons, one that was with Emma and one that lived in the neighborhood. I just think all the other evidence, things stated by the show runners and the writers, suggest that they are one individual, the same one we have always known, just now they have cursed memories. Though, like you said they did split Regina, into the Evil Queen, so that they could give a sort of, but not really happy ending to Robin and Regina. All i am saying is it is possible even though all the other evidence points to this being the Hook that has been on the show since Season 2.