Folks we are talking deep cell batteries. They are made to hold and give power over an extended period of time. A cranking battery is made for a burst of high amps over a short period of time.
Look at all the charts you want but here is my experience first hand with deep cell batteries.
I have been running bass boats for years with trolling motors that totally drain a deep cell battery in a days use. These batteries if kept properly will last 3 to 4 years before degrading to a point that you need to replace them to get a full day's charge in them. But they still will take a charge. Many boaters when replacing the boat deep cycle take the old boat batteries and put them in their camper.
What kills a battery is heat. Amps and heat have a direct relationship. If you run your trolling motor continuously on high you are pulling high amps and it will overheat a battery or in an extreme case even melt the posts, this will destroy your battery quickly. So in your RV if you need AC, Microwave, block heaters, water heater, space heaters, or anything that generates heat and brings your amp meter over 20 amps for more than a minuite you should have the generator running.
My goal at night when sleeping is under 5 amps. Which is the fan on the heater and the light bulb in the water bay along with a few lights.
The trick to longer lasting deep cycle batteries is to keep them charged and do not subject them to really high sustained discharges.
An AGS is an awsome tool for keeping batteries topped off. Someone told me they had a problem with the cost but if it will extend the life of your batteries, and limit the hours on your generator and the need for service then it pays for itself really quickly. It also keeps you from waking up in the middle of the night and having your OCD force you to check the charge level indicator.
So replace that ceramic heater in the water bay with a 40 watt light bulb, change your interior bulbs to LED's. Leave the factory preset on your AGS alone, 11.2 amps will not kill your deep cell batteries.
Above all check the water level in your batteries often and use only distilled water in them.
Once you have fed your amp OCD you can then work on your Water OCD. And to make it all fun you can even spend a bit of time on your Propane OCD.
An RV'r is someone driving a $300,000.00 Motorhome towing a $40,000.00 car and looking for a free place to park.