Rustle,
Shortly thereafter the 3 become 2 in the grand scheme. (Known and Unknown or some such)
Back to my Mode S comment. If everything is required to have Mode S then ATS will accurately know the position of everything that flies. The only other factor is whether its intentions are known to ATS. As that can only have two possible answers, there can only be two possible classes of airspace. There cannot be any Class U and class K has to go to the surface. So sounds to me that one hand of some regulator doesn't know what the other hand is doing.