The gist of the article is that Watterson was a guest artist on Patsis's Pearls Before Swine comic, and drew some panels on three of the daily strips. Ironical

The gist of the article is that Watterson was a guest artist on Patsis's Pearls Before Swine comic, and drew some panels on three of the daily strips. Ironically, the strips reveal why Watterson was so successful, he was an excellent artist in a time when most newspaper comics were illustrated poorly or with idiosyncratic but only functional art. However he really only excelled in the Sunday comics, which gave him room to express his wonderful art; the dailies were much more friendly to the functional art he stood as a counterpart to. I don't think he has any intention of returning, though. I'm more surprised he hasn't worked on anything at all since then; you'd think the graphic novel format would be more amenable to him because of the control he could have; his comic days seemed to be one fight after another with the powers that be.