Not many people worry about de-thatching (or thatching according to video below) their lawn here in Georgia. According to the video it is fine to do once per year or so. I don’t think it is a big deal unless you have a lot of clippings lay on the grass. For instance, if you over fertilize and don’t cut often enough you can develop a thatch problem. There are attachments to pull behind your mower so if you have any size lawn at all I suggest that instead of a thatch rake… unless you have an energetic teenager. 
