Neither consciousness nor mind are primary in the MWI - so I can't see where you are getting that from.
Its not an explicit form of Primacy of Consciousness like prayer or wishing. Its implicit in QM and its basic premises. One example of an implicit form of PoC is to project properties or aspects of consciousness onto reality and treating them as metaphysical and not epistemological factors. I think the ancient philosophers got hung up on this when debating whether a color like "red" was in the object or subject. This went round and round for a few hundred years until someone pointed out that its both (form/object distinction).
Jaynes covers simi...
Eliezer Yudkowsky and Scott Aaronson - Percontations: Artificial Intelligence and Quantum Mechanics
Sections of the diavlog: