Para 5.2.2 says do the 20% with AGMs. It also says do not Float them if you charge them more than once a month. (Not sure about that!--anyway there it is)
It does not say why to do the charging profile recommended.
https://www.trojanbattery.com/pdf/TrojanBattery_UsersGuide.pdfIt does not say you have to recharge them from when they are low enough to do a bulk stage. It does not discuss what to do if you only ever do shallow cycles with AGMs (unless I missed that) Usually you are told with Flooded batts that you should do a deep cycle every so often if you only usually do shallow cycles.
Most people AFAIK, just buy batteries and do what is reasonable and then buy new batts when needed. That's what I do with my car. I only fuss about my RV batteries. Not logical, but how it is!
