Dick,
Its time for you to admit that in relation to the myriad alarms that go off on controller screens, that you really have no idea on how and why they go off. As I have stated TAAATS is a machine, the alarms go off where the machine thinks there may be a problem, not when all defences have been breached.
We have STCA (imminent collision risk, usually when aircraft are self separating after being given traffic),RAM (aircraft outside the flightplanned corridor, usually when aircraft are manouevering for approach OCTA), MPR (missed position report, aircraft not reported within 3 minutes) CLAM ( mode C disagrees with reported level, usually due signal garbling) and others. If I had a dollar for everytime a system alarm went off in Brisbane Centre, I kid you not, I would be a very rich man and not have to work. You seem to have blind faith in your supposition that alarms only go off when there IS a problem.
I have asked before and will now do so again. Get your US and Australian controllers to come on these forums and give us their FIRST HAND views on your second hand quotes. Ask your Aus controller mate how often the alarms go off. Could you name him/her on here or quote their experience.
Don't forget there are 11 000+ controllers in the US ( supposed to be about 13 000 but we'll leave FAA stuff-ups out), and about 750 in Australia, leave aside all the arguments about traffic density, and lets think about what the sector sizes must be.