'''SPOILER WARNING STILL APPLIES MASSIVELY'''
* AlternateCharacterInterpretation
** Mitch, the BigGood, in accused in-story of having and using MoreThanMindControl abilities just like the BigBad. He's also accused of using a memetic weapon to make Thomas Muoka an {{Unperson}}. The OptionalCanon origin story for him indicates that he was lying to his allies. Canonically, he ''sacrificed our entire universe'' to imprison Oul in the chronologically first chapter of the story (higher-dimensional beings like Xio generally don't believe that life can exist in only 3+1 dimensions). He also personally ran a {{Dystopia}} (albeit to save humanity) and wiped out human civilization at least 20 times. And in the end, he got to go home alive, unlike ''every single other named character''. Suffice it to say, he has a bit of a spotty record.
*** Just before the end, Mitch/Xio angrily asks Ching what he should have done instead. Ching's answer, as is often the case in ''Fine Structure'', comes by way of demonstration; the same decision Jason Chilton made: [[HeroicSacrifice sacrificed]] ''[[HeroicSacrifice himself]]''. WeCouldHaveAvoidedAllThis, if only Xio hadn't been too selfish, or afraid, or perhaps simply incapable of considering trading its own existence for one dinky little 3+1 universe and its future.
** It's said several times that a year and a half of total sensory deprivation should have (and in a sense, did) utterly destroy Anne Poole's mind. "Marooned" reveals that being restricted to 3+1 dimensions has a similar effect on Xio, cutting off nearly all of its senses except Mitch's meager five. So why doesn't Xio go completely insane (by its own standards, if not humanity's)? Maybe it/he ''did.''
*** WordOfGod says Xio wasn't mentally affected because the subjective time was very short to him. All those millenia in our universe amount to only an eyeblink in terms of five-dimensional time.
* DesignatedHero: By WordOfGod.