The Met's ct exercise appeared to go well. They picked a lovely day for it. Always good to do, these exercises.
Outside London it's worth remembering previous experiences. Eg. Michael
Ryan (Hungerford), killed 16 people and injured a further 15 at random in under an hour,
including the first police officer on scene. With that rifle, if he
could see you he could hit you. A neighbour just asked me about police
response times to such incidents and if there were sufficient officers. I
said a force has, on average, less than 5% trained for firearms duties.
She replied, "but we never see any police patrols anyway".
I told her not to worry.
Rule 1, reassure the patient. :-/