One thing that the original article pointed out, is that Rockwell emphasized facial features as part of his signature look. For a more exaggerated example, look

One thing that the original article pointed out, is that Rockwell emphasized facial features as part of his signature look. For a more exaggerated example, look at faces in anime or Disney animation. IMO part of why Rockwell's images continue to resonate is that he uses exaggerated features sparingly, to draw your eye to a particular part of the image. Looking at the composition, the overall work is photorealistic, except for the features that he was trying to have viewers focus on. Look at the faces in his paintings, they clearly aren't traced over photos. However, large other parts of the illustration do appear to be traced or painted over photographs. Selecting what to emphasize and how to blend it is true artistry. It is a partial shame that most of his output was spent on commercial work, but at the same time that is one of the main reasons he was so prolific.