....and that's what it's all about - teamwork. No one is out to get one another (I think). This thread is a very good one indeed.
On the subject of R areas and numbering, I think they are split up for ease of assigning them as operating areas for aircraft inside them.
Dick - Thanks for the info re 'green between'. On a lot of current sectors, that would be 5NM anyway by the time you got the screen resolution. Smaller sectors would help, and that means more people. Not going to happen for a while I would say.
Cheers,
NFR.