Here's my take on this. Let's say I paint an image of Batman on canvas. (Just because I enjoy playing with these powerful pop images.) And as I'm painting a particular line on the canvas in acrylic, I realize I am duplicating a line originally rendered in India ink on paper, a technique used in comic book production in the Golden and Silver age. And this style of ink line (thick and thin) evolved out of neccessity - after all a line had to be thick enough to render on cheap newsprint after being reduced - and not get buried in the colored ink - but not be too thin so as to be lost or lose their impact on readers.
So the ultimate images we remember from the comics of the 60's and 70's actually grew out of the medium itself as much as the imaginations of the artists. Cheap newsprint printed in a given size (for economic reasons) pushed creative boundries and became the mother of invention. So the image I am painting then is not as much the "message" asis the medium of comic books which made neccessary a certain kind of line style, a certain way or working in ink and a particular way of generating blocky primary color fields.
Often the medium rules. Try using a a fine tipped ink pen on a cave wall and that will give you some idea of how this works in real life.
(Painting shown is by the author, Batman In The Abstract #2, 24" x 36" 2008) For an enlarged view, click on the image.