I am of the view, and I have been of that view for many years, that there are thousands of parish records that the NSW BDM has not indexed. They did not start to process the ECRs until sometime in the 1880s, ie up to 100 years after some were first recorded. They have not ever finalised the reconciliation of the civil marriages 1856-1895, to the parish registers, although they started that process in around 1912, ie around 100 years ago.
Several years ago, together with a Church archivist, I located a particular parish register that had been returned to the local parish in the 1930s by the NSW BDM, apparently after all the entries had been transferred to the NSW BDM. Ummm.... the Archivist and I spent quite a deal of time establishing that NOT ONE of the entries appears on the online NSW BDM index, and nor are they on the "Pioneer/Federation" index/CD etc. 800 events, at a particular C of E church in the City of Sydney, all should be in the ECRs and NONE are. Together the Archivist and I contacted the NSW BDM and offered to arrange to re-supply the information. I hope that when the NSW BDM's revised indexes come online that these omissions will be displayed.
On the other hand, I have at least one mc from the ECRs, a real deal certificate issued to me in the 1980s by the NSW BDM, personal attendance and my own cash too, they didn't accept personal cheques, I can assure you that the online index does NOT have that mc indexed. It is findable on the fische index. NSW BDM have my email address, and a scanned copy of that certified certificate, and to date, they have not altered their online index. I had sent the scanned copy at their request umm.... much earlier in THIS century
. I did receive an acknowledgement "read receipt" thingy for my email.
Sorry for the side track, but NSW BDM online index does have some flaws.
Cheers, JM