Upon closer reading of the rule, it appears that in most cases you would be playing with fire even if you came close to running your tanks down to the new requirements.
We would be used to using something like a 45 minute reserve at the cruise burn rate (45 litres in a C206 as an example).
Now (for day VFR at least), they are requiring 30 minutes at "holding burn rate" (something like 25 litres in a C206). Not sure I would be too comfortable letting my tanks get down to those figures in any case (even with modern guages and fuel totalizer).
CASA's supposed intention was to make things safer, but if everyone starts using this 30 minute holding rate rather than 45 minute cruise rate, then CASA might be disappointed to find the outcome of their 'new safety requirement' is more fuel exhaustion incidents/accidents.