Just thinking about the practicalities.... if NATS/ CAA are responsible for air space and security are trying to save lives by preventing terrorism, then with the restrictions in place choke points are created, so more chance of a midair collision which could result in loss of life, atc will only offer a basic service who then is responsible for the midair /, the PIC for look out, but could it then be argued in court that if the choke point were not there would the accident have happened. Will we see an increase in midair collisions operated by spamcan pilots with head in the office transfixed on a GPS for fear of deviating from the permissable airspace for fear of being "shot down" or fined. I just think there is a safety issue in these restrictions and I'm not sure a midair could solely be put down to PIC look out. if not then maybe the "lifesaving" security organisation will have to pick up the tab and explain themselves to the families. Are olympic spectators lives more valuable than those crash on in a village hall 30miles away ?