I am still waiting on having the trident control the dos 100% but I am happy with the trident in general. It has definitely shed some light on consumption. I am still trying to figure out how the trident determines how much to adjust the dos up or down. I don't see where you input the tank size so it can calculate what is required to adjust the dos.
I wonder if it doesn't need the exact water volume because it would just add some, re-test, and then decide if the values are within your tolerances or not. If not, the Dos doses more, and the process continues until it falls within your preset parameters. If it tests alk being too high, it just skips dosing until it falls on it's own. It seems like the Trident is keeping things within a pretty tight window.
Just speculation on my part, but I think it has to do with how tight the Trident is striving to keep things in your specified window.