What is your current watering schedule and what was it during the spring and summer? Frequency and duration?

How long does it take to get an inch of water (measure with cat food or tuna cans)?

How shady is your lawn?

How high/low have you been mowing?

When were the last two times you fertilized and what did you use?

Have you had any problems with disease, insects, or weeds? Did you treat with anything, and what did you treat with?

You do not need to aerate. Do you have any problems with water running off when watering? Soil should normally be pretty hard when dry. Does the soil feel hard after you have watered?

Can you post a close up picture of the grass blades taken in the shade (cloudy day)?

Deep and infrequent watering and higher mowing heights will promote deeper rooting of turf grass.
Turf roots grow late into the fall months and much root growth occurs in spring/early summer. Fall application of potasium can help root health and late fall (winterizing) fertilization helps the plant store cargohydrates that the plant can draw on in the Spring during the root growth period. It may sound counter intuitive, but not fertilizing in Spring actually helps promote root growth as Spring fertilization causes top growth at the expense of rooting. So the more energy/food the turf can store in late fall for use in the Spring, the better.