Lets assume a demon model, which move simplified part of me in trillion different copies. Is it a problem for me? No. It is logical to conclude that it will do it trillions times, so I will eventually return into my original myself, and will not notice any difference.

I'm not sure I understand.

It will be some kind of natural selection in dust world lines, which will result in more stable ones, and most likely I am already in such line. In this line dreaming is built such that it will not result in important shifts of reality. And it is true: dreaming is not unconsciousness state. I start to have dreams immediately than I fall asleep. So dreaming is built to be not interupting some level of consciousness.

Yes! This is it! Thank you!

(Is this also evidence that Dust Theory/MWI is true? Or can it be explained through some other phenomenon? It seems that it might be- it's why we aren't in a 'perfectly' stable existence, i.e. one that did not involve sleep at all, which would be extremely hard to enter. Also it solves the Doomsday Argument, since transhumans wouldn't sleep.)

Someone may try to use the flux nature of reality for magic. You must close your use, forget everything about your self, imagine that you have 1 000 000 dollars, forget that you imagine it, and just keep this feeling. Than you open your eyes it would be more likely that you have 1 million dollars. While it seems to be ridicules procedure, it strikingly similar to traditional human magic, which always include trance state and visualisation of desired things. If natural selection exists in dust world lines it would help beings able to rise its reproduction chances by magic, so nothing surprising here.

No, if your subconscious could anchor you in reality than you couldn't eliminate the knowledge entirely from your perception just by concentrating really hard. You would need to use nanotech to completely destroy the idea, which is a way I suggested of escaping the death of the universe.

You do not need Dust theory for all it. You could get flux reality from some interpretation of QM. Just imagine that you live inside large Schrodinger cat.

I'm not familiar with the Copenhagen school... can you describe this in more detail? How is it analogous to Dust Theory?