Or you could just look at your Trimetric when you run something and not have to guess on efficiency and such, as he was running his tests on the 110v side.
155ah out of the 550 watts of solar, is on the high end and would require very good sun, as it is very close to the 30ah per 100 watts max that most of us have heard, and seen in typical RV systems. A couple cloudy days, and he will be in trouble, I think. Lost of theory and calcs, but I wouldn't take what he says as very good information, I think. Too many weak spots like checking SOC with voltage and no mention of loads being on, etc.
I think he needs to take a look at a solar calculator, like in this discussion.
With this you can calculate the theoretical max output for your panels for anywhere and anytime. It is very useful to see how much you lose with location and time of day, and is a repeatable method for checking if your system is working properly.
Most of us have probably done similar power use, solar gain calculations for our systems over the years, and most of them probably have underestimated power use and over estimated solar gain.