How can you take details of a flight plan if you are also separating traffic?
As a rule I shouldn't be. I don't mind if I've got the time.
Don't you need the have pretty well immediate communication to pilots of aircraft you are separating?
Yes, absolutely. As an ATC you can 'control' most of the comms but there are certainly occasions when 'shut the F up' is uttered under your breath.
When I have explained our present system to US controllers they say I must be mistaken
When you spend a bit of time over there, flying & watching what they do, it's (and they are) remarkable! What we do here wouldn't work over there.
Could this ever cause a breakdown of separation or an accident? Why do you reckon other countries have separate VHF frequencies? And why do you reckon AsA closed the outlets down?
* Yes, it certainly could (in extreme circumstances). You put measures in place to not get to that point but.........
* I'll take that as rhetorical! you are 100% correct.
* I think we all know the answer to that.