Dog One, you're being a bit harsh there. As you are aware, VFR do not need to be even on the R/T in E, however they are encouraged to monitor the E frequency. The only way they are going to find out if they are going to get speared by a jet launching out of a Class D CTR is if they get told by the jet they are on the way before takeoff. The first call on Centre after takeoff doesn't cut it either: "Bla Bla Bla Climbing to FL340, DONDI at 35". Hardly enough info (or time) for Joe VFR at 6500ft flying past Broome to make any decisions about a confliction and then announcing.
So a broadcast on Centre during taxi is understandable. QF does it too sometimes. As for workload, the same taxi broadcast would have been made had the Tower not been there so I can't see why the Centre freq would become chaotic.
The fundamentalist NAStronauts, of course, will argue that TCAS will save the day. That's the TCAS in a non-radar environment that probably has never been checked (or is it on?).
All a result of the NAStronauts insisting on E over D.
Problem solvered when ADS-B is mandated for all aircraft soon.
No more broadcasts required.
Whilst on the subject, CASA hasn't caught up with a broadcast prior to entering E on descent either. We have to make one into G, so what's the diff with descending into E?