4 weeks ago I aerated, dethatched, mowed very short and sweeped all of the grass and sent to compost pile. Even after doing this, there was a bit of dead grass left behind. I figure this will work good seed to keep things moist, kind of like a natural mulch. The next day I rented a Billy Goat slit seeding machine (set it to the #5 setting which is more than the suggested overseeding setting). I bought 50 lbs of commercial seed (supposed to overseed an acre), the same seed I had seeded professionally 5 years ago. It came in great back then. I have ~7/8 of an acre minus house, deck shed, etc. I of couse ran out of seed before I was able to do it all, but the lawn that I didn't't get to didn't't really need any help. I went over the yard twice, 90 degrees of each other. With the dought this year, had a large area of bare dirt where the grass never came back. After 4 weeks I am seeing just a few new sprouts coming up. I've watered 3 times a day to keep the seed moist and I am disappointed with the results. A couple of areas that I broad-casted the seed and raked over are filled in great, but the areas I slit seeded are no so good. Any ideas of what I did wrong?