@jparansky , that recommendation comes from the average weather data recorded at Raleigh State for July: a daily high temperature ranging from 69-90F, with a total of 4.28 inches of rain/month. With that kind of rain, you probably don’t need to water much.
Still, if you’re having an unusually hot or dry July, or if your lawn is just looking thirsty, consider raising those times. The city of Raleigh recommends no more than 1 inch of water/week (see http://www.raleighnc.gov/services/content/PubUtilAdmin/Articles/WaterConservationAndEfficiency.html) , which is about 40 minutes/week with a typical popup sprinkler head, and that’s not counting rain. For that temperature range, 15 or so minutes every 3 days shouldn’t be too far off, and if you get a lot of rain, Weather Intelligence can skip those days anyhow.
I wouldn’t recommend raising the frequency (times/week) too much though–it’s much better for your lawn to give it deep waterings once or twice a week than to give it shallow watering every day. If you see runoff during those longer waterings, I’d turn on Smart Cycle, which will deliver that long soaking in little “gulps” that your soil can handle.