A357575,
As with much of the CARs and CASRs, it is a mess.
However, look at it from say, Jetstar's point of view: If the position of safety pilot is not recognized by CASA, then he/she can be rostered H24/7, think of the productivity.
In the old QF system, the time was recorded by the records system as if the safety pilot was the operating F/O, with the totals of co-pilot and Total Aeronautical Experience added to as "normal".
I have never understood the anal approach taken to anything to do with pilot's logging time in Australia. For gaaaadds sake, please don't start on ICUS again.
Tootle pip!!