When I was in the service I was project officer on the upgrading of the brigade's control room in one of the shire birgades, in fact the project came up with the solution that enabled regionalisation of control rooms.
One of the factors that we looked at was the efficiency of the control staff, I am not referring to how well they did their job which in line with all the control staff I have worked with, was of the highest standard. It was the number of calls handled per operator. We established the minimum number of staff we needed to be on duty which was three. One to handle the incoming call, one to handle the radio and one to supervise. Working on the usual crewing formula that allowed for leave, training, meal breaks etc. we needed 5 per watch. I worked out a comparison between the number of calls handled per operator in our brigade verses the number of calls handled by a operator in London and not surprisingly the London operator handled far more calls than ours did. We did look at several solutions to this one was to combine our control with that of the Ambulance service and another was to combine with neighbouring brigades. The reason these initiatives failed was political the chief officers did not want to lose 'their' control rooms, the ambulance service failed when a chief officer went on record stating that the fire brigade should take over the ambulances. The system we deployed was capable of doing both these roles and for a period we did work an arrangement with another brigade where our emergency control would be set up in their control room and their control could run our brigade whilst our staff evacuated to their control to take back the function. It worked in exercises, fortunately it never had to be put into action for real.
The principal is sound and there are obvious financial advantages for non metropolitan brigades.
The argument about local knowledge is a red herring in that ever since the days of phoning or running to the local fire station controls have always relied on some type of database whether paper or computer based to mobilise the correct attendance. Mistakes have happened given the number of 'High Streets' or 'Church Lanes' they are inevitable but these happen regardless of the size of the brigade.
What does concern me is the reason and the way the regionalisation project is being run. The background seems to have more of a political agenda rather than the practical one and the government's track record of this type of project is not good.