No Dick it comes from claiming a saving on paper despite all evidence that more money was actually spent. We have many people that claim a saving when in reality it may cost more... Take sector consolidation from PH, AD, DN and SY into BN and ML as an example, did it save a cracker or cost many?
How many FIS people got made redundant, yes it was a one off cost but did it get counted against the 'savings'? How many got retrained into ATC, how many succeeded in that training, how many got VR at the end of the retraining? How many got moved to AUSFIC, or training roles etc. Did this count? How many Smelly's (said with love) are still in the game? How many of the large (staff) reductions were "actually realised". How many extra ATCs were needed to absorb the FIS jobs? What was the final FIS number before it got assimilated ie circa 1997 numbers in FIS not 1990 numbers? Has there been an actuary look at the numbers and 'prove it'?
Most of 'this money' will be saved (cough, sic, spew) by not replacing RAAF equipment at some point in the future... But the same facilities will need to be purchased now for fitment in the civil system ( ie new equipment needed to move the existing RAAF APP units into the civil units.), hence it will save 5/8ths of bugger all in reality. Then there are all the triggers for redundancy, relocation, training etc.
As for ATC numbers, RAAF have their number, Civil has their number, both sides are short (allegedly), short + short = still short... This may actually need more staff. Reason RAAF ATCs are often co rated they provide APP and TWR services; to take the APP function and put it in the civil system means you lose all the co-ratings and your staffing requirement may go up?
Having said all that is it a good idea to integrate, IMHO hell yes, but will it cost more or save money; my own money is on the first element if anyone is keen to take a bet.