I have done some deep tine aerating but do not have long experience with it. My opinion agrees with others who posted in this thread: it is a good practice to have in rotation or alternate with other types of aeration. The underlying soil is important. I don't think you are going to have or cause any problems putting sand over just about anything. The important thing will be to continue doing it once you begin that program. As you probably know, the kind of layering that really causes problems comes from using a heavy soil over a lighter one. I like washed mason sand, but strongly prefer to have a small amount of OM cut in when using over soil based fields. Even with the best intentions using straight sand you are dirtying things up when you aerate aggressively anyway. I had a physical analysis done on my mix. Generally, it was very good. The only suggestion they gave me had to do with the total percentage of the sand component on adjacent sieves; mine was 80.6% medium and fine (.25 mm and .15 mm). They suggest this number be no more than 75% and that, "if possible," I increase the amount of coarse sand (.5 mm) "to improve the stability of this mixture for root-zones." It really is not possible for me in an easy or affordable way. I believe the small amount of organic matter I am using helps. I think he only commented on it because he knows I used this mix when I repair compacted areas, such as in front of pitcher's mounds, as well as for topdressing.