In his latest post on William Gaddis's The Recognitions, Bud Paar remarks that
The world Gaddis created is ours, a look in the mirror, certainly, the way a good comedian can be so funny because they make fun of some little quirk that we identify with because we thought that idiosyncrasy was ours alone.
It is notable that Bud compares Gaddis to a "good comedian," because it is often overlooked that Gaddis is a very funny writer. (If anything, JR is even funnier than The Recognitions.) Certainly it's true that Gaddis has a reputation as a "difficult" writer, and "difficult" often translates into "heavy-handed," or "deadly serious," but it's also true that Joyce's Ulysses is a "difficult" novel, which doesn't prevent it from being one of the funniest books ever written. In my opinion, those who accuse such books of being inaccessible usually mean by it that they aren't plot-driven in some obvious way, or that the authors don't signal to us clearly enough "what happened," or at least how we're supposed to interpret what happened. Such impatient readers don't seem to realize that most of these ostensibly difficult works are essentially comic novels, their comedy intended as a kind of substitute for other more obvious "entertainment" devices.
Indeed, many of the postmodern mega-novelists--Barth, Coover, Pynchon, even some of DeLillo--are basically comedians, and would, I'm sure be quite content if one of the lasting judgments of them as writers was that they wrote some very funny books. This doesn't mean that laughter is the only response readers might have to their work, but it does mean that the critics of modern/postmodern comedy ought to themselves lighten up a bit. Postmodernists want their books to be enjoyed just as much as any formula novelist; although the comedy in these books can sometimes be unsettling, even extreme, finally they just show us how much of human existence is mostly worth a good belly laugh. And even that most notorious technique of postmodernism, self-reflexivity, is really as much a way of poking fun at the pretentions of fiction writers, their claims to adequately represent the world of experience in a direct and unmediated way, as it is to frustrate the expectations of unwary readers. Although admittedly it is also way of mocking the sobriety of a certain kind of reader, who can't finally accept that even serious fiction might occasionally aspire merely to tell a good joke.
(Bud points out in his post how Gaddis occasionally pokes fun at himself as well.)