AT SOME SHOWINGS of Nashville bands of people squirm in their seats, flamboyantly discontented--sharp out-takes of impatient breath, exclamations of disgust, even boos at the end of the show. It had to come to this: it should have been obvious from the beginning that the colossal build up for Nashville would alienate people, and not just because certain aficionados consider it the height of sophistication and the mark of a properly iconoclastic sensibility to reject on principle whatever happens to be snared by the cover of Newsweek or Time.

It had to come to this, because the critics and the friendly folks at Gulf & Western (owners of Paramount, which distributed the film) seemed determined to push Nashville, even though they'd never liked that weird Robert Altman before, and had a hell of a time trying to figure out what to say about his new film. So when the onslaught of praise rained in, as much as for any picture in recent memory, it just about ruined the effectiveness of the film itself.

High expectations tend to be deadly with any Altman film. Most movies shine when their openings become public events--it's a long tradition for the two to intertwine. Some filmmakers almost appear to anticipate it. In Jaws, for instance, half the punch of the first scene comes from the publicity. Knowing what's going to happen makes an innocent event like a young woman skinny-dipping on a summer night doubly frightening. A movie like laws thrives in the public eye because it delivers the goods. The Exorcist procliamed that it had a couple of jackpots--the crucifix, the flying green vomit--behind curtain number three, and it had to be seen to be believed. Everything else was just garbage--the eleven bad songs to fill out the hit single album. Jaws was more refreshing than. The Exorcist partly because it didn't pretend that the filler was anything else but a vehicle for the real stuff.

Nashville doesn't have any "real stuff," and as a result some critics had trouble talking about it. One might call them the cookbook critics--their theory is that the secret's in the ingredients. Just as the studios make movies like salad, adding a sprinkle of "love interest," a dash of "violence," a pinch of "fun," so the critics think of "plot" or "action" or "climax" as separate components to be inserted in a movie at will. "Bad language," for example, is a poor allocation, no matter how it's used.

SO THEY COULD never quite figure Altman out. "This is boring--it never goes anywhere," they'd say. "Why, you could put a camera in someone's living room and come up with this!" They had no idea of how to get a handle on the amorphous mass of an Altman film, even when they began, finally, to stop dumping on him. California Split, for instance, they found vaguely respectable. California Split was a journey into gambling culture--how desperation and betting work at the tables, at the track, and in people's lives. The language of the film was energy cycles--how people key up and run down, how they invest energy and spend it. The theme was abstract and didn't need a story--the plot was unimportant, events didn't have to connect in conventional ways. Much of the undercurrent of ebb and flow was achieved by Altman's technique of using multiple-track microphones, so an audience could hear half a dozen conversations in a poker palace at once, or hear someone out in the half as easily as the person at the next table.

Altman junked almost all the conventions the cook book critics go for--except the stars: he held out and focused on two major characters, Eliot Gould and George Segal. And even though both actors turned out excellent performances, they almost spoiled the film. It was as if they'd been given too much freedom, because Gould's happy-go-lucky interpretation made Segal's tortured gambler seem cliched, as though his problems were silly. Segal undercut Gould, too, making him seem shallow. With the actors canceling each other out like that, the film became curiously objective.

The cookbookers, of course, were all over the actors. "That's it! It must be a male camaraderie movie!" Male camaraderie was very big last summer, and suddenly Altman was playing the Newman-Redford. Woodward-Bernstein game. Depending on what: they thought of the picture, the critics had California Split down as a good army-buddies film, or a poor take-off on The Sting.

But with Nashville, they were in trouble. What do you do with 24 characters? Now Altman was making explicit his concern for making movies about communities rather than internal personal conflicts. And the California Split problem was solved. At last the let's-get-high-and-decide-what-we're-gonna-shoot-tomorrow theory of handling actors could operate the way it was supposed to, without eager stars killing each other off. Now they could follow their own instincts about a role, because, there was no intrinsically dramatic situation for them to get caught in.

So Henry Gibson's Haven Hamilton could be vain, phony and tyrannical, a civic leader and country star apparently treating like children the audience that fed his ego. Until he stands on the stage of the Parthenon oblivious to his wounded arm, thinking of the audience before himself. "This isn't Dallas, this is Nashville. Let's show 'em what we're made of!" If one's inclined to make value judgements about specific moments here, the gesture is either redeeming or it is not. But Altman and Gibson developed the character in a less good guy/bad guy way. He is merely a man who defines himself through his audience--a totally public identity. This may be courage: more likely his soothing of the flock after the assassination is a method of control: Altman's last shot in the film, before he pans up to the sky, is of a policewoman, prim in her cap, marching through the crowd with a bag slung officially over her shoulder. Maybe the singing Haven Hamilton is a kind of fascist.

As usual with Altman, it depends on what the color of your glasses is at the time. Either "It Don't Worry Me" is a stirring cry of survival, or the horrible chant of a wired mass for whom murder doesn't matter. Or a million other things, but the cookbook crowd tried frantically to answer this question, because the only anchor they could find in this plotless, characterless, messageless mass was that Nashville was about "America." America is very big this summer, maybe, but it's a frustrating theme for people accustomed to motion pictures telling them what to think. They find themselves babbling absurdly when they try to talk about it, often because they can't face what the film keeps making them fear.

Joseph Kraft was the funniest, frantic in his role as the guardian of the nation's self-image. In a column called "Nashville, the motion picture, tries--but fails--to tell what's wrong with America," Kraft points out the danger of trying to sum up the country. Indeed, "the analytic tools shaped by the likes of Marx and Freud have come to grief trying to define what's wrong." Leading into an interpretation of the film, he writes that "the film's view of the nation's flaws is so general and so wrong that it seems useful to identify the weakness in the argument."

The weakness, it turns out, is that in Nashville the characters don't have real choices to make, they are trapped in a society without decisive options. This is a view of America "in a pig's eye," he says. In fact, the Nashvilleans represent "a tiny segment of" American life. "These people do not have real decisions to make. They concern themselves chiefly with appearance and image. If they fall, they must move on. Inevitably their lives are hollow, their values shallow," Kraft admits that sometimes, "on the campaign level," politicians may concern themselves with image to the detriment of the people, but most of American politics and American life is characterized by "different, indeed opposite features." One wonders what he was doing from 1968 to 1974, or whether he ever cast his syndicated eye upon the White House transcripts, but aside from this, one gets the sinking feeling that the "choices" he refers to in America are the choices of the free market system--where you can buy whatever color car you want--and the electoral process--where you can choose between the Republican and Democratic parties.

But Mr. Kraft can rest easy; Altman evades the trap of defining America. Indeed, in making Nashville, he jettisoned (with a couple of exceptions that mar the film) the last obstacle to making a purely descriptive movie: he junked the concept of the filmmaker himself. Opal, the BBC reporter, busily chronicling American and acting sillier than the Nashvilleans, is a parody of Altman. And the cookbook critics, trying to get a grip on themselves, string adjectives together searching for how to sum up.