Speaking of Star Wars, are mitichlorians (or whatever) really necessary when Bones figured out how to give Jim psychokenetic ability with a thyroid derivative?
I think you'll find that writers always give themselves an out, for why the miraculous solution that works in one episode doesn't work in the next.
It's one of the reasons I like the writing in the fanfiction Parahumans/Worm Universe. That rule above gets tossed, but the result is that there are so many actors onstage in such a complicated plot-maelstrom that you don't mind if a few of them get permanently offed.
In the case of Jim and Bones, that phenomenon only worked on that planet, if I recall correctly.