A small but perhaps important point. In my original post summarizing the EO, I had this to say:
What if the person is not a security threat, but happens to have potential intelligence value? This is not a proper ground for continued detention under the PRB system (I believe this is different from ARBs, and hence a substantial difference between the two systems).
Upon reflection, I would say it’s not at all that clear. The language here is a bit tricky, and I might be wrong about this point. But since the substantive test is that continued detention must be "necessary to protect against a significant threat to the security of the United States," I suppose it remains possible to argue in a particular case that the test is satisfied where a person is not likely to be dangerous if released yet could be the source of important information if held in continued detention subject to interrogation.