I think the CPC amendment is more clear in terms of a process that would happen in providing a list. It doesn't require the extra.... It's more specific.
I was going to comment on an earlier point. The way I understand this would function—and John can clarify for me if I'm misunderstanding it—is it effectively provides another option in terms of ID. For the vast majority of people, in addition to a prescription or some other form of ID, this provides another way of proving residency in addition to the vast number of other ways that are available.