I have a 2007 Coachmen and the same valve/city fill configuration to fill my tank (I think they call it a WaterWorks panel). I think what someone said above re: the overflow is correct...I'm pretty sure you have to have a fresh tank overflow (or you'd end up with a vacuum in the tank as you used it). We try to keep an eye on the tank when filling, but sometimes I get busy prepping something else and space it for a minute. If it fills while I'm not paying attention, it just starts flowing out the overflow onto the ground under the RV. No harm done. We hear the splashing on the ground and turn the hose off.
Anyway, I know you're looking for data (which I unfortunately don't have), but I thought it might help to hear from another Coachmen owner about how we fill. We know we have a 50 gallon fresh tank (black and gray are each 28 gallons), but we don't base our actions while filling on that info.
Slightly off topic, I'd be curious if your system actually works to use the pump to draw antifreeze in like the manual says. I couldn't get that to work and when I asked our local Coachmen guys, they were baffled. They said based on the way it is plumbed, there's no way that could work. I got the manual out and asked "then why is the procedure described here?" and again...baffled. So, I would have liked to use that functionality to draw bleach in for sanitizing at the beginning of each season, but turns out it doesn't work. Hopefully yours does! I just pour the bleach in the hose before connecting it to the RV...