I haven't seen Wise's book so can't comment on what he states. The paint on the tags seems consistent with the degree and thickness of the paint on the rest of the inner fender. The tag was held on by one screw until sometime later in the assembly process, therefore only one screw is painted. Maybe the tags were rotated by several different assembly line workers as the car moved down the line, and they looked at it from different angles depending on what their job was, so that would be why the tag was only held on by one screw?
And some tags seem to show evidence of a slight bend by the corner near the painted screw, it might have varied depending on how the worker looked at the tag. Some workers might have been rougher in their handling or twisted it up to view a code better, and others didn't?
As far as the inspection tags, they weren't on every car. I'm not sure if they were even on most cars. Maybe someone has studied that, but unless you are restoring a car that has an inspection tag, there is no reason to add one.