I would mention that besides my way being easier to
write the necessary introspection code, it will also perform
better as it does not have to walk the namespaces (which I think can be an important consideration here.
We could also make the signature be
ad_proc -callback acs_user::change_stat -implementation dotlrn { ... }
and have the namespace we end up giving it be an
implementation detail not exposed to the user.
