Oz controllers the worst?
Nah, it's only the system they have to work and secure their jobs with. Bugger!
I'm sure that the APP people know the difference between 10 and 5nm separation (and then some); unfortunately they are not permiited (MATS) to apply it.
Now take for example ORD or DFW - 5nm REALLY means 3nm - if you can't do, go to ARTCC - same general rules for Oz but if you have to move metal (a la USA), you have to ratch it up a gear.
Having said that, Oz ATC rules do make for inefficient flight profiles - even LHR (you know - Mary Poppins, bad wx and even worse food) seems bloody efficient by comparison. (Actually it is - they run you to 2.5nm separation).
Thankfully for both sides of the microphone, Oz FIR is not too often visited.
