This paper is directed at the important contribution to fluid dynamics made by Johan Nikuradze. His seminal paper published in 1933 represents the gold standard of empty conduit permeability, for the flow of water through roughened pipes, even to this very day. We revisit in some detail the "inflection profile" in Nikuradze's plot, which appears in the curve for his roughened data found in Figure 9 in that publication. In so doing, we show that the data points at low Reynolds number values, and

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... particularly those surrounding the value of 3.4 approximately on the x-axis of his plot, do not represent the reported experimental results found in his tables of data. Furthermore, we also demonstrate that this discrepancy in his original paper is very problematic because it forms the basis for many subsequent scholarly works. As a result, this inflection profile has become erroneously embedded in conventional folklore concerning fluid flow in closed conduits and has enjoyed widespread acceptance as being a legitimate feature of fluid dynamics dogma. With the advent recently of Quinn's Law, a novel approach to the understanding of fluid flow in closed conduits, we are able to articulate in a manner not heretofore possible, the significance of this discrepancy which is far too important to ignore.