Originally Posted by
junior.VH-LFA
I really fail to see (as someone who operates IFR out of Class G daily) how this is necessary or could be justified in Australia with our traffic density.
If there's traffic, talk to them. It's really not that hard.
That is exactly the big sky theory. Talking works most of the time, there have been a few instances where talking failed, and we were reliant 100% on big sky theory. There are almost certainly more we never hear about.
The problem is, accurate navigation i.e. IFR effectively makes the sky a lot smaller. That is why ATC was invented.