Scenario is being forgotten here.
Yes, batteries need 14.8 to be properly charged, but all we want here it to put some AH back in, not to properly charge the batteries. That is done elsewhere by other means.
With generator recharging we do 50-90s and not even try to do the 90-100 on generator. You do the 90-100 on shore power or with solar.
Alternator charging is done on an opportunity basis if driving around anyway, or else when parked as a desperate way to restore some AH when the batts get too low and you don't have a generator. You would have to be crazy to try to properly charge your batteries with alternator charging.
The issue then is to get "enough" AH into the house batteries with any alternator charging going. How much is "enough"? How long is a length of string?
