@moodler writes:
I am liking this idea of having two or three clearly-defined levels of openness it might be practical for the reality of very large and evolving data sets …
Specifically in response to this, let me point out that in the aforementioned paper we work out a few non-mutually exclusive ways of turning fine-grained data on openness into more categorical judgements (and we point out the risks of relying on the most reductive approach of all, a hard binary judgement):