Most likely it was not; the official 5-D was a dark neutral gray. The formula is on the bottom of the second page of this 1941 memo, showing none of the ultramarine blue that was used in the other paints which did have blue tones to them (second page on this memo). There was a conversion paste (also neutral) that was mixed with old stock of the pre-war gray to "convert" it to a 5-D appearance (albeit the formulas were different) and this version of dark gray might have had a slight blue tinge to it as the #5 Standard Navy Gray had a blueish tone, but I have to believe that the chroma value would be so low as to be invisible. THat's just the opinion of a non-color specialist though, so take it with a grain of salt.