In relation to Bill Sethare's work, I recommend listening to example (1) here : http://sethares.engr.wisc.edu/html/soundexamples.html , which is an amazing demonstration of the relationship between overtone beating and consonance / dissonance.
Even if the statement "lack of beating between overtones sounds good" doesn't hold true as a universal rule (and I'm sure this has occurred to many people prior to Wilkerson), you can really see what Helmholtz was getting at here.