Sammie: I would be very very surprised if the TIW was not honored even if it was not coded in the reservation---as I said, it would violate the "never say no" principle, and that's pretty deeply ingrained in the corporate culture. The only way I could imagine it is if Disney puts it in the published materials, and even then, it would be phased in over a few months until word got out.
Even if it is "official policy" not to accept it, I'm guessing the cast members on the ground will still do it to make their own lives simpler unless and until it rises to a terminable offense (much as some of the
DDP shenanigans have.)
Instead, I suspect that the "enforcement" will depend on strong words and peoples' inclination to follow directions. But, I've been wrong before.