Now you could just bite this bullet. You could say, “Sounds to me like it should work fine.” You could say, “There’s no reason why you shouldn’t be able to exert anthropic psychic powers.” You could say, “I have no problem with the idea that no one else could see you exerting your anthropic psychic powers, and I have no problem with the idea that different people can send different portions of their subjective futures into different realities.”
I think there are other problems that may prevent the “anthropic psychic powers” example from working (maybe copying doesn’t duplicate measure, but splits it gradually as the copies become increasingly separated in information content or in location; I think my comment here might provide a way to think about that), but “the idea that different people can send different portions of their subjective futures into different realities” is not one of the problems, as I believe it’s implied to be possible by the “two Schrodinger’s cats” thought experiment (https://phys.org/news/2019-11-quantum-physics-reality-doesnt.html, https://arxiv.org/abs/1604.07422, https://web.archive.org/web/20200215011940/https://curiosity.com/topics/adding-a-second-cat-to-schrodingers-cat-experiment-might-break-quantum-physics-curiosity/, and the Frauchiger-Renner thought experiment mentioned in https://www.quantamagazine.org/frauchiger-renner-paradox-clarifies-where-our-views-of-reality-go-wrong-20181203/). (I’m not completely confident in my understanding of this, so please let me know if I’m understanding that thought experiment incorrectly. My understanding of the experiment is that the different participants should rightly expect different things to happen, and I think the easiest explanation is that the participants have their measure going in different proportions to different outcomes.)