Sounds like you have a good grasp on the cultural practices... It is true that thatch has a dual definition... the main one is the living roots and stems growing above the surface of the soil and matting in with dead plant material... It is caused largely by improper cultural practices,,, so the question I ask myself in addressing thatch is which cultural practices are responsible for causing thatch in the first place... then I counteract those all season long and aerate in the Fall... In most cases aeration isn't necessary either, but it doesn't remove OM from the turf and it makes the clients happy... I don't believe that in most case the clipping even return 25% N to the turf, let alone 1/3, but I could be wrong about that... the important thing that grass clippings do is provide feed for microbes building soil structure and preventing our thatch problem... Once wequit encouraging grass roots to grow upward and provide healthy water/air ration within the soil structure, we are half way home in dealing with thatch... What do you see as encouraging the type of thatch discussed here???