Where does one go to look up report R42729? Does it say flat out there is "no correlation" between low tax rates and economic growth? Dr. Sowell quoted those presidents over the last century who believed the paradox of low tax rates/higher revenue held good over time, and also cited the experience of Iceland and India to support it; he specifically noted that "it doesn't always have to be that way."
As a guiding principle and not a panacea, it does seem to make sense. If the main effect is indeed to provide a bigger piece of the pie to the wealthy, is this something we want to interfere with as a matter of policy?