A low height of cut largely eliminates thatch as long as N is kept moderate. No 1 lb N per month applications. Once I have scalped someone's lawn, I never have to do it again. I contrast and compare to homeowners and landscapers not mowing low enough in addition to putting on too much N. Annual thatch removal becomes part of their life. Where I am at, Zoysia does not go dormant at all. It might grow slower from December-May, but it is always growing. From June-October, it is a PITA to mow. I end up using 2X rates of Primo on Zoysia to stop it from growing over an inch of leaf in one week. Mow it higher? Then you get grass that grows 3 or more inches per week and develops tremendous thatch. When there is a lot of thatch, there is a high possibility of developing Large Patch by Novermber, when it is normally cloudy, raining and cool all of the time.