No-go areas!
John, are you seriously minded to think that public areas that just happen to be in the vicinity of an air display should be emptied of those who have a lawful right to be there?
And what about those members of the public who are there for any number of other reasons, perhaps a family picnic, unassociated with any air display that just may be happening in the vicinity? Should they be moved along too, or for that matter, why not close all nearby roads and empty houses, schools and hospitals? Perhaps also farmers in the vicinity should be prevented from tending their land on Airshow day?
It ain't gonna happen and as a former display pilot myself I don't think it should happen. We're not talking about the Olympics or the London marathon here, where national interests might trump the interests of a few, we're talking about a local fete in comparison.
There are better ways of mitigating here, and I am sure that the CAA will eventually tighten up some of the slack that I know, from my display days, existed in the regulation. They might also want to reconsider the relationship that exists between those charged to oversee air display flying with those who actually operate the participating aircraft. In my day there was a lot of seat trading done between overseers and operators, and a lot of blind eyes were occassioned to be turned for favours dished out.