Sure, when you scale it up to the something the size of a city, then you can say "We want to be able to handle X major incidents at the same time over the entir

Sure, when you scale it up to the something the size of a city, then you can say "We want to be able to handle X major incidents at the same time over the entirety of the city." My point is that X will continue to shrink (as has been the trend for decades), but never hit 0, and you can only consider a limited area before response times become an issue (even if you somehow got to the place where you were very confident there would never be more than one concurrent fire in the UK, obviously you couldn't reduce staffing to a single company).