Then I don't see how you are disagreeing with me at all, because that's pretty much the crux of what I'm saying. The state |R>|R>+|L>|L> causes its individual particles to behave differently from how |R>+|L> behaves, and that is trying to tell us something about the cat paradox.
I am having trouble believing that down-converted electromagnetic radiation disobeys Maxwell's equations.
If you analyse a vertically polarized plane wave impinging on the 2-slit/CP/VP setup using Maxwell's equations, you will get a diffraction pattern. To say that you will not get a diffraction pattern is to violate Maxwell's equations.