First, here’s the picture.
To summarize the text here: Norman Rockwell first created the sample abstract painting, painted a cutout of the man, positioned the two paintings in his studio to make sure that the effect worked, then painted the whole thing. He then took a portion of the original painting, submitted it to a Cooperstown Art Association competition under a different name, and took first place. That’s the part that makes me laugh; I dearly love stories like that.