Always wondered what portion of the irrigation cost was really to avoid "some browning" in drier seasons. Somewhere between 1977 when I entered the biz, and 2000, the systems mostly seemed to be designed for green no matter what. In tech terms, they were designed for 1" per week (typical need) and if demand got to 1.5" a week, or 2" a week, you browned out. Or, you ran more sprinklers during the day to catch up (watering from 10A-6P now illegal is some spots) Now, I think many systems are designed for at least 1.5" per week, applied at .2" per night, everywhere.
I once asked a veteran super what the biggest problem/risk of extending irrigation into the afternoon hours on those really hot days. He said it was the some of the old guys might strip down and run through the sprinklers naked.......who wants to see that?