I seem to be having the same problem and without wantIng to hijack someone else's post with my first,I will give you some background on my problems.
last year I had to build a driveway at the house we had been in for about 6 months, while the mini digger was on site I dug over the garden to a depth of about 18 inches and removed a fair amount of large rocks concrete and other muck you get in the garden of a 1970's development soil is high clay content but I've seen a lot worse, there is now very little if any large stones or rocks under the surface. The soil was raked over and left to settle for 6 weeks, before the turf was laid it was raked again and compacted. A good friend of mine with a very good lawn helped me lay the turf, it was not walked on and regularly watered, bear in mine how much rain we had last year!
The result was very weak patchy grass that I then over seeded, this still did not seem to work. I've got a Hover mower for spring and autumn for a higher cut with less weight on the grass, a cylinder mower for summer which is set to it's highest setting, both are sharp and I feel I'm doing all I can including, regular feeding, aerating in spring along with removing thatch with the lawn rake attachment of the mower. I really am starting to feel depressed each time I cut the lawn as it looks awful, I never cut more than a third of the length at a time, we have no pets or children to run over it. If the forum allows I've a link to some pictures
Ps my ipad seems to be auto correcting with all sorts of words so I hope it all makes sence!