Jeff King [off-list ref] writes:
There's another mention in Documentation/technical/api-object-access.txt.
Yes, and we are on the same page on that one.
But since the entire API is undocumented, I'm not sure it matters much.
That file has been a placeholder since 2007. Maybe we should just delete
it; its existence does not seem to be guilting anyone into documenting,
and these days we'd prefer to do it in-header anyway.
-Peff