I have read quite a bit of McLuhan; I also read the monograph by Harold Innis that inspired him. What did McLuhan have to say about creativity, I ask myself?
A great deal. He viewed artists as seers or clearsighted analysts of society. In The Medium Is the Massage (1968), McLuhan writes that "the poet, the artist, the sleuth--whoever sharpens our perception tends to be antisocial." That is, they are not "well-adjusted": only they can "see environments as they really are." The well adjusted are the people who cannot see that the emperor wears no clothes (88). Furthermore, he argues in Understanding Media that "Art at its most significant is a Distant Early Warning System that can always be relied on to tell the old culture what is beginning to happen to it” (22).
He may have understood artists to be people who are able to represent that which is normally not considered representable. To illustrate the idea that a medium itself can be a kind of message, he says "An abstract painting represents direct manifestation of creative thought processes as they might appear in computer designs" (13). I am not exactly sure what he means, but I think he means that certain kinds of art are not "content-laden" but rather "medium-laden" or "form-laden." An abstract artist, therefore, can articulate something that McLuhan aimed to teach others to see--that the media of communication are themselves worthy of study. An abstract artist thus is a theorist of communication insofar as she takes seriously the medium (electronic impulses, if you will) that permit the artist to conceive of art in the first place. Certainly self-awareness is important to some extent for creative people, even if their aims are practical (creating art, rather than studying the act of creation).