He also wrote, in the introduction to the comic (http://www.scottmccloud.com/1-webcomics/chess/index.html):
My fourth online comic seemed to strike a chord
with many readers, despite requiring side-scrolling
as well as down-scrolling (which I'll admit, can be
pretty annoying).
It sounds like this was something experimental; remember, this was the early days of webcomics. He was experimenting with what you could do in a new medium. It turns out that this choice was kind of annoying; but it was a nice experiment, and it's a good comic despite the somewhat annoying scrolling.I also wouldn't be surprised if there's some hidden meaning to some of the movements.
The repetition of regular squares sets up rhythms, that he then violates for purposes of mood, emphasis, timing, etc.
*seriously, his second comic about comics, "Reinventing Comics", basically boils down to "the Internet will transform the finances behind comics via micropayments" (right on the transformation, wrong on the micropayments) and "the Internet will transform the layout of comics by freeing us from the constraints of a particular page size".
Scott McCloud wrote a whole book explaining why, "Reinventing Comics: How Imagination and Technology Are Revolutionizing an Art Form" ~ http://www.amazon.com/Reinventing-Comics-Imagination-Technol... a quick summary: he's trying to redefine & elevate comics from being mere cartoon strips in newspapers or the plastic covered, pulp superhero "comix" you find in dingy comic book stores to a higher art-form through new technology & imagination ~ http://www.scottmccloud.com/2-print/2-rc/index.html
I don't know about chess but it seems to follow some kind of pattern when zoomed out.. Is it a famous game or set of moves?