Great stuff everyone, thank you! Took me a while to get through all of it, but worth it (even though some of it is still over my head).
I am hoping that this (2) 100AH battery setup allows me to stay above 50% DOD for my short trips, then I can just plug it in to shore power when I get home to give it all the time it needs to get back to 100%. From what I gather, it seems like I would actually be doing the batteries a disservice by charging them back up here and there (but never getting back to 100% SOC) with the trucks alternator. No reason to recharge if the batteries are not at or below 50% DOD. But when hooked up to the truck, the truck would be charging every time you drive around regardless of what % DOD the batteries are.
How long does charging (2) 100AH batteries take compared to charging (1) 100AH battery? The same?...twice as long?...somewhere in between?