I think it means we should look beyond our "applications" of certain products with their specific claims and figure out what is actually happening beneath the surface of the grass and the actual activity generated by these products... So-called 'organic' products will not react to every soil the same way and certainly can be rendered useless by counter-productive cultural practices such as irrigation and mowing wet soils... http://www.cmg.colostate.edu/gardennotes/213.html "The term soil tilth refers to the soil’s general suitability to support plant growth, or more specifically to support root growth. Tilth is technically defined as the physical condition of soil as related to its ease of tillage, fitness of seedbed, and impedance to seedling emergence and root penetration. A soil with good tilth has large pore spaces for adequate air infiltration and water movement. (Roots only grow where the soil tilth allows for adequate levels of soil oxygen.) It also holds a reasonable supply of water and nutrients. " The real question is: Do we think 'tilth' matters in lawns? or does dumping the right stuff on it make all the difference??