... it's as if the real Michael has emerged, instead of Michael being changed by circumstances.
Pete, I agree. I've posted elsewhere that each of Vito's boys had certain of Vito's genes (characteristics), but not all of them. Sonny had Vito's violence gene; Fredo had Vito's sensitivity gene; Michael had Vito's destiny (I really don't like that term) gene. In other words, Michael possessed most of Vito's genes, but he just could not manage them to have the effect and effectiveness that Vito had.