Guptar,
Just have a look at the Trans Tasman Mutual Recognition Treaty section of the Australian Civil Aviation Act 1988, versus the NZ equivalent, to see how much legislative work CASA has put in, to make certain that the benefits of the TTMRA are not enjoyed by the Australian aviation sector.
Also, recall that, at the behest of the unions, Keating as PM (yes, the TTMRA is not "new") the TTMRA was, aviation-wise, virtually unilaterally suspended until 1996 (Howard government) but such is the power of "the mystique of aviation safety", that well known CASA political security blanket, that the promise of the TTMRA in the Australian aviation sector has never been realised, and is not likely to be.
The NZ approach to regulation of aviation has been an outstanding success, to the degree that it has been copied by a number (rising) of smaller nations, with very great success.
The NZ aviation sector, compared to Australia, is booming, including international contract MRO, which, thanks to CASA, has almost all been driven off-shore in Australia. And don't anyone come the raw prawn about "it all labor costs", unless you can convince me the Germany is a low wage country.
In the MRO sector, it is CASA rules in practice that completely stifle productivity compared to NZ (and almost anywhere else). That is the basis of the biggest cost difference between Australia and NZ, and makes Australia hopelessly uncompetitive.
CASR Part 61 is putting what remains of the contract airline pilot business out of business.
Tootle pip!!