The Coulter principle: Imaginary origins

In the opening session of CYTO 2013 a spokeswoman for the Wallace H. Coulter Foundation summarized from the podium a story, styled as an urban legend true so far as was known, of Wallace Coulter working toward sizing pigment particles but finding his paint sample frozen. He then supposedly thought of the similar viscosity of paint and blood before first demonstrating the Coulter Principle using his own blood. This requires Wallace being ignorant of the commonly-known disparity between the viscosities of paint and blood, and several listeners subsequently asked me if this story could be true.