[Mike K]

The factory paint was put on after proper preparation - clean surface, primer, undercoat and top coat, maybe several coats.
Yes that's generally true but:

I am having a dig at the Canadians now ha ha ! The NOS cab 12 Ford doors I purchased from Camberwell, these doors had a green painted directly over bare steel , no primer at all , I was amazed that the bare steel inside the doors had no signs of rust .

Getting back to the poor paint , I doubt that they had actually totally solved this poor quality problem until well into 1943 or 1944, that's if they ever did finally solve it . There would have been thousands of vehicles painted in the lower quality paint before the army's complaints were looked into.

Reading the NAA files. There is a message from a navy destroyer ( Stuart I think ) asking their HQ, something like this 'what type of camoflage paint, if any , should we paint our ship with '