It all comes flooding back to me now. I've been so busy I'd forgotten that this was all debated to death a while ago.
It was about Australia 'going it alone' rather than waiting to see what the rest of the world, or at least a substantial part of it, is going to do.
I see no point in Australia spearheading a technology that may turn out to be a unique and therefore unnecessarily expensive orphan. The imperatives that resulted in an Australia-unique DME system do not exist in respect of the functionality that ADSB is intended to deliver.
I remain with Dick on this one.