ALTHOUGH ONE PERSON on the scene says that "the Texas literary demimonde is all adither because Larry McMurtry came out with guns blazing and attacked everyone in the Texas literary establishment," McMurtry himself is a bit annoyed by that assessment. "There's no controversy yet," the author of Horseman, Pass By and The Last Picture Show says firmly. McMurtry, also a Washington book dealer, adds, "But there probably will be, when the article comes out. . . . If there's any it's going to be then, not now."

The article McMurtry is referring to is an approximately 8,000-word piece titled "Ever a Bridegroom," scheduled to take up the entire October 23 issue of The Texas Observer, a well-respected Austin fortnightly. Says The Observer's Joe Holley, "We're traditionally focused on politics and so it'll be a gauge to see how interested Texas folk are in their writers."

But how, if it hasn't yet been published, can it be generating dithers? The answer is that in mid-September in Fort Worth, McMurtry delivered the entire article as a speech to a "spill-over crowd" at a local museum. Ever since that evening, rumors about the contents of "Ever a Bridegroom" have been as thick in the state as discarded cans of Pearl.

Larry Swindell, the book editor of The Fort Worth Star- Telegram, was there. "He categorically put down Texas writing and Texas writers, dismissing them individually and collectively as having produced no literature of lasting value." Texans, McMurtry and others feel, have a sentimental myth about themselves, having to do with sagebrush, lonely towns, good-old boys and other folksy trappings, and writers are mired down in it despite the increasing importance of city life throughout the state.

What bothers Texans most about this native son's attitude is his disrespect for a triumvirate of now-dead literary heroes: J. Frank Dobie, Walter Prescott Webb and Roy Bedichek. It's un-Texanish, if not downright dangerous, to imply they were softheaded, overrated hacks. McMurtry also examines Katherine Anne Porter, William Humphrey, William Goyen, John Graves, Max Crawford and William Brammer, among others, mostly puncturing Texas pride along the way.

In the mid-'60s, in an essay called "Southwestern Literature?" McMurtry questioned the very existence of such a thing and sounded a rallying cry for young writers to create one. Curmudgeon, iconoclast, critical conscience, whatever, McMurtry waited well over a decade and, as far as he's concerned, no one took him up on his challenge.