It would be better to index the earlier material direct from the original entries because the indexes do not include the woman's name until after 1900. I think some of the older certificates have actually been filmed - does anyone know about this?
At some point it would be good to assemble a consolidated index of baptisms & Marriages missing from the IGI; e.g. illegitimate children some of whom the LDS entered under the mother's suename, BT's for Marown, Lonan etc; early Registered Births and Methodist Catholic and other Non-Conformist Baptisms.
Just a thought.
Nigel