I came across this in my saved files as it made me go "hmmm."
Other than the obvious conclusions regarding different soils, I'm not sure if there is anything else that can be concluded, but I'd like to know what influences (from a plant growth perspective-the "why?") the methods had and if there is anything regarding aeration that is applicable to an established lawn.
Anyway, I thought it was kind of interesting and would share it:
http://arkansasagnews.uark.edu/593-13.pdf