It doesn't matter. It is a part of RET.
It does matter, a lot. First, because "RET"
does not exist. There is no theory named like that and basically no theory that deals with that subject anyway.
If "RET" is just your colloquial term for
all science then it's a pretty bad one. Is cancer research part of RET? Is manufacturing technology part of RET? I'm thinking you'll say no.
So what qualifies as "RET" in your eyes? Because, if we take it after the naming, it should only concern the shape of the Earth, right? Or do you just call anything you don't believe in as "RET", so that FET can have a nicely lined-up antagonist?
Dark energy does not concern the shape of the Earth in any way.