Thanks for that, Drew. I'm trying to understand how smart chargers work and have tentatively concluded that they apply the bulk charging voltage until the current falls, then drop to a lower voltage. Or stop altogether as my Black & Decker charger does. As you point out, there may be a considerable current going to RV appliances so this method is denied to the converter charger. Sometimes the Black & Decker starts again so maybe it is deducing something from the voltage while not charging, even drawing current from the battery?
If there is a way to deduce state of charge from voltage without waiting for an hour or two for the surface charge to dissipate, it would be very useful to RVers without battery monitors.
My amateur idea is that the battery bank itself should be made smart by counting amp-hours in/out and have the means to signal the charger what voltage is appropriate. As a satisfied user of a $25 battery monitor I believe this could be done at very reasonable cost up front and an overall saving because of better charging and increased battery life. Arduino microcontoller chips cost less than $5.