Erik, that is fantastic clarification - thanks.
Would my question “Would in fact fewer ‘without stickers’ pics be OK, covering everything but with less fanatical overlap?” be true?
Jonathan, that looks brilliant too.
“projector with 0.5 throw distance lens” - why necessary, and how does that work? Is that really close-up to the wall? Sounds like the projector is intended to be moved around as photography progresses? Is the projector close-up so as to project a really bright image? How would it work in a daylit room - pattern still visible? How would it work with flash as the main exposure-light source?