Hi John,
Your comments about the VDS not just being used for supercells is interesting. I'm wondering if this changes from state to state? I've only seen the VDS comment for Sydney and Brisbane regions, and anytime it's been used it's always been a supercell (and a well structured one at that). From my observations, a 'VDS' is used for supercells, but not all supercells are given a 'VDS.'
There are many times when the warnings have listed a spotter (or public) report but no VDS has been given.
I'll go one step further to say, from observations, the 'VDS' is used when significant low level rotation is being detected in the storm by doppler (ie, it's the Bureau way of saying 'this storm may produce a tornado'). But I know of two storms this year to buck this trend a little...
And yep...the Kurnell radar is a doppler (implemented for the Olympic games).
AC