OzExpat:
I've deliberately been staying out of this discussion QSK.....
OzExpat, mate, my previous post was calling for your participation in this subject only because of the high respect I hold for your knowledge and opinions on all things relating to PANS-OPS.
Distilling the comments in your last post, as well as the posts from others, I would appear that CASA/ASA may need to also consider publishing (certainly for those ILS approaches in non-controlled airspace) a DA based on forecast QNH and then also shading the box to indicate to the pilot that the DA can be lowered by 100ft if an actual QNH is available (+ PEC of course). Is that how it works in PNG?