davidearl (2016-07-11 14:58:27+00:00): Now, that *would be* tagging for the renderer! I really don't think that is the answer. (Nor is "operator" on its own, that's not enough information).

Cambridge University is not a campus University. There are about 10 areas you might call campuses in the conventional sense, maybe, and also 30 or so University colleges, which are independent institutions which are also part of the University but not operated by it. There are numerous smaller "campuses", in the limit being individual properties, or areas within other properties (of which these hospital ones are just a selection). For example, this: http://www.openstreetmap.org/way/48910156 is different only in scale, not status. If I try to take your logic to the limit, there would be no amenity=university in for University of Cambridge, because there is no single amenity. I chose to take it to the other limitwhen this was all first mapped in 2011.

I don't think by making a change here you're going to get the answer to your "use case" you want anyway, because Cambridge University (and indeed others, it's not unique) just doesn't fit your model of an institution in one or a few large campuses. It is way more complicated than that. It seems like you want to re-engineer the data so it provides the answer you want to get, but I'm not sure the question makes sense in the context of this institution. Are you counting Campuses? If so, by what judgement is Douglas House less a Campus than, say, Homerton College, or the "Silver Street/Mill Lane site"? And what about co-operative ventures? Or if you are counting University's you won't get the answer 1 for us, short of completely re-organising it all as a single relation, because of the multiple campuses and collegiate system. You'd either get zero or a dozen or so, or 50, or 1500 or so depending what you look at. You also can't say that a building isn't a university because some universities (not Cambridge, obviously) *are* single buildings.

A relation which contains all the University premises might be an answer, but it would probably also need some new tags, which identify campuses or property areas, as opposed to buildings, and similar. It's really hard to maintain relations though, and it really doesn't add anything to the information, it's just a different way of grouping. building=university has been suggested, but it doesn't solve the problem of things which aren't buildings like the hospital ones, and it means the building can't be tagged as anything else (e.g. a residential block which is university premises). amenity=university_premises or some such might work, but then requires everything else that understands universities to change.

But theses all require someone to make an investment of significant amounts of staff time and real money to cope with non-upward-compatible change.

I did think about the way the University is tagged long and hard before I did it, and published the method. The interpretation of amenity=university in the way you want to make it largely post-dates that.

(Whatever else, just locally changing some blobs in the hospital area inconsistently with the rest is surely the worst possible answer.)