Watering: Deep and infrequent is the mantra for watering. This is for all turf grass all over the place. Deep means 1 inch all at one time. Put some cat food or tuna cans around the yard, and time how long it takes your sprinkler(s) to fill all the cans. Memorize that time. That will be the time you water from now on. My hose, oscillator sprinkler (full sweep) and water pressure takes 8 full hours to fill the cans. Your time will likely be less. I like gentle watering. As for watering frequency, that depends on the daytime air temperature. With temps in the 90s, deep water once per week. With temps in the 80s, deep water once every 2 weeks. With temps in the 70s, deep water once every 3 weeks. With temps below 70, deep water once a month. Note that you have to keep up with quickly changing temps in the spring and fall. This deep and infrequent schedule works in Phoenix and for the most part, in Vermont, so it should work for you. The reason for deep and infrequent is to grow deeper, more drought resistant roots and to allow the soil to dry completely at the surface for several days before watering again. If it rains, reset your calendar to account for the rainfall.

If you change, and I think you should, you cannot go cold turkey. Your grass roots are too short to deal with deep and infrequent. They don't need to go any deeper because they get water so often. Wean them back to once every week or two. Start by skipping a day and water every 3 days for awhile and water a little longer, once a day only.

One factor you might have to deal with is low humidity. Of course Phoenix has low humidity, too, but keep an eye on the grass for signs of wilting.

Yes, and I'm aware of all that but with my situation, having clay about four inches down, if I water any longer than 15 minutes (less actually), the top soil saturates and the water runs off once it hits the clay. So deep watering is not possible. The recommendation with this situation is to water for short periods and then repeat after an hour or so to give the water time to penetrate down into the clay. That is what I'm doing. My question is...

What does the thick, apparently wet or spungy, texture of my lawn mean? I'm wondering if it means the grass is getting too much water. Maybe I should drop back to every three days.

Your situation reminds me of what mother used to say: "If your friend jumps off of a cliff would you follow?". I think the bottom line is what is best for your yard, not what is the recommended frequency for watering.

If there is that much water in Your yard, obviously you are watering to much. I would let the yard dry out so that it can be walked on with out squishing. Once the yard is dry, monitor it closely, and water when the grass starts to stress. Based on the information you collect you can determine the rate and frequency that is best for Your yard.

I am unfamiliar with the rain fall pattern in your area, but that is the starting point for your watering plan.

I always find it amusing driving around the neighborhood when it is raining seeing people's sprinkler run.

To establish the watering plan you may wish to buy a moisture meter. There are many for less that $20. DON"T rely on one reading take the time to monitor a dozen places in Your yard. The moisture levels may indicate watering one area more than the others.

@dchall_san_antonio, is there a good way to tell that it is making a difference in the clay other than an improvement in the lawn? In my planters for instance, the clay is hard as a rock when dry and impossibly thick when wet. If I added surfactant to the clay in the planters would I, after three weeks, have soil that is more loam like?

With the surfactant, water should absorb in and not run off.

Also you can check the "hardness" using a screwdriver. Stick a screwdriver into the ground before you put the surfactant on and then 3 weeks after. It should go in much easier after the treatment. If it is easier but you want it to be easier still, do the surfactant again.