First of it seems the power is in the system adjusting to weather, and watering in order to forecast what is needed dynamically. The Fixed schedule does give that ability. The Flex monthly doesn’t make sense because it adjusts duration and regardless of time of year it should take the same amount of water to wet the root zone. So that leaves Flex daily.
I live in the desert so have a lot shrubs on emitters and it seems that this system was not really designed for this usage. First of all a measurement like Area in sq ft makes no sense when you have emitters on individual shrubs. What does that even mean? Secondly emitters are in GPH and no idea how that translated into nozzle inches per hour or if it even does translate. I can’t really find anything on the web site that is aimed at this very common usage in xeriscape. And yet it seems the system could be ideal for xeriscape. I also have no idea what crop coefficients are, as I can’t really find a definition or strategy for setting this value.
In some ways it almost seems like this is overly complicated and most people can’t even figure out what these values should be, and settle for the default. It seems that far fewer better defined variables would be much more useful. For example on a camera there is the concept of Exposure Compensation. It lets the camera guess what the exposure should be but if an actual picture looks off, you simple add or subtract what the camera thinks without trying to guess which of all the variables should be tweaked slightly. It seems this is far too granular, and therefore is a complete mystery to most of the user base.