True. Jonathan Van-Tam was saying in the daily briefing a few days ago that they are definitely not relying on this as a magic bullet, there will have to contin

True. Jonathan Van-Tam was saying in the daily briefing a few days ago that they are definitely not relying on this as a magic bullet, there will have to continue to be substantial old school manual contact tracing. I think if we did know exactly the mechanics of transmission then we could afford to be super minimalist about how much data was disclosed and restrict it only to the very least required. The problem is that we don't know what that minimum is. I think one difference between critics of this approach (and indeed Google/Apple) and the NHSX/Ministerial decision makers here is that the former are not accountable for controlling transmission. If it doesn't work then they tried to help and regrettably it didn't work. The latter are trying to thread a course between how many people will die, how many years we'll be paying off debt or suffering from economic chaos, and privacy implications. That doesn't mean we can just ignore the latter, that is too easy and only leads in one direction, but it also means that decision makers have to balance competing concerns. If it were me (but I am neither an expert nor do I have the full set of data that they do) I would pursue the same course as they are but also have a team working on an alternate implementation as a plan B. I would also make binding public commitments about what we would do with this data, introducing new statute law if really required. Again though, that's easier said than done because they don't yet know exactly how they'll need to use this data.