David,
Bravo for the smart decisions in the conversion process you describe. You are not alone- some of the biggest financial institutions on this planet continue to use ancient Cobol apps. Why? Because the business justification to rewrite it again does not exist. At least one of those banks says it saved over a billion dollars by ignoring Windows!
Regards
j.R
"... They ne'er cared for us
yet: suffer us to famish, and their store-houses
crammed with grain; make edicts for usury, to
support usurers; repeal daily any wholesome act
established against the rich, and provide more
piercing statutes daily, to chain up and restrain
the poor. If the wars eat us not up, they will; and
there's all the love they bear us."
-- Shakespeare: Coriolanus, Act 1, scene 1