Brilliant idea, but "case" is redundant, and upper/lower is incomplete, so there should be:

text-transform: CASE; text-transform: case; text-transform: Case; text-transform: casE; text-transform: cASe; text-transform: CaSE; etc...

I've wanted the latter to write headlines about NeWS and NeXT and NeRF.

That's very neat. You'd probably need two words to represent camelCase. And then that might be hard to disambiguate from your `CaSE`.