Sorry, I should have specified I'm using Flex scheduling, though I suppose that's apparent now. I'm using a weather station at a nearby small airport in San Diego county (CA), about 3 miles away. While my micro-climate is consistently 3 or so degrees warmer, the weather should be pretty accurate.
The fescue typically waters every 4-6 days, the St Augustine every 6-8 days. The planters run about every 5-8 days.
I may have understated the apparent water loss/stress. I've been overriding the system to give more water by forcibly depleting the soil moisture level to zero when the grass/plants/etc look stressed. The fescue (for example) is starting to look stressed again. It watered this morning but the grass doesn't look any better, so I assume it's still stressed?
I read the provided links. They describe what I'm seeing better than I did: "... the blades will fold, which shows the lighter blueish green underside." I mow down to at about 2"-2.5", but that's per Marathon: "Height: Summer, 2-1/2" mowing height recommended. Winter, 2" mowing height recommended." Is that wrong?
Two days ago, I changed the root depth for the fescue zone from it's default 6" to 5", which seems to have moved the watering schedule up to every 2-3 days now. I hadn't thought of changing the MAD, but I'll do that instead, since it's more accurate to leave the root depth as it should be.
For lawn care, I use Marathon fertilizer about every 6-8 weeks. I use a 25-5-5 (as directed), except around late October and again in mid to late march, when I use their 15-15-15. In San Diego, it doesn't "cool off" until Halloween (that's roughly the last day you can wear shorts at night). And by mid march, the cool weather is over. Both fertilizers are rather instant and not a time-release formula. I have 12 month general and manganese fertilizer spikes for palms (in the corners of my fescue lawn) and 12 month citrus spikes around my lemon tree. The other planters get some of the 15-15-15 about 3 times a year (late October, March, July).
I'm open to further suggestions, and appreciate everyone's feedback and input.