Two Plane Vs. Three Point Gaging and Roundness

A non-round (pseudo-round) workpiece can mike as if it were round using only customary two- point, two- plane gage;
A pseudo-round can be detected with a three point gaging system;
Given the number of lobes from using a 90 degree V-block and indicator, a savvy shop hand can choose the proper included angle V-Block to determine the difference between R and r;
Salvage of individual parts is possible given sufficient stock to remove;
Bars exhibiting lobing can be ground to the next incremental size and the lobing eliminated with attention to details of wheels settings, support plate location and geometry, and rotational speed.