THEY STRUT, they hoot, they roll their eyes, they wiggle their hips, they cake-walk, they drool, they cry. At times, the cast of "Ain't Misbehavin'" parts the curtain on their flummery to pay a solemn tribute to a man who symblized the high times of the Harlem of the '20s and '30s.

"Ain't Misbehavin'," a musical based on the muscial leg-end of composer and pianist Thomas "Fats" Waller, does the same thing the Harlem era it celebrates did: dish out the fun and bypass the facts. No one seems to mind. This year "Misbehavin'" captured every theater award available to a musical, including the Tony Award for Best Musical. It was the play President and Mrs. Carter chose to see on their last trip to New York.

The format, a revue of familiar songs; the setting, the by-gone era of top hat and tails; and the conveyors, an all-back' "cast, are now very familiar and profitable, as suggested by the popularity of "Bubbling Brown Sugar," "Misbehavin'," "The All-Night Strut" and "Eubie."

Despite the richness of their source, however, the plays are all malnourished. What happens is that the lives of the people who gave the substance are glossed over by the glow. And the whole historical and sociological significance of these pioneers is overlooked.

"Fats" Waller, along with his mentors, James P. Johnson and Willie "the Lion" Smith, set the style for a generation of piano players. Waller was there at the peak of popularity for piano rolls, for the early black musical success on Broadway, when the record compaines turned to race music, when Hollywood turned to race musicals and when radio opened up for blacks.

A large man physically - 5 feet 10 inches and 285 pounds - Waller also was a legendary boozer and eater. In his day most of the jazz critics dismissed him because to appeared a tool of Tin Pan Alley as he ciowned and shuffled through performance after performance.

But "Fats" had a sly, courtly way of answering all the criticism, "One never knows, do one?"

A sad footnote to the good-time memories evoked by plays such as "Misbehavin'" is that life has been erased by the passage of time. All of the musical monuments of "Fats" Waller's days are gone.

The Lincoln Theater on 135th Street, where Waller got his professional start, is now a church. The Lafayette Theater, where the best of black talent was show-cased, including the 1937 landmark production of "Macbeth" by Orson Welles, is now a church.

The Savoy Ballroom, where the youngsters of the 1930s and 1940s danced all night to Waller and his proteges, is now a string of storefronts. Even his birthplace at 28 West 134th Street was mashed in the highrise growth of central Harlem.

Only three places associated with Waller's personal life are still standing.Abyssinian Baptist Church, where the minister's son, Adam Clayton Powell Jr., snuck Waller in so he could practice the organ, remains. And the brownstone home of James Johnson, the great stride pianist, and the other rowhouse Waller shared with his second wife are still standing.

Most of the neighborhood between 132nd Street and 140th Street, the hub of Waller's Harlem days, looks at best unkempt. In this neighborhood today the Harlem Hospital, Schomberg Research Center and the Lenox Terrace apartments seem to be only oasis of activity.

Of all the nightclubs that made Harlem a password for high living - Connies's Inn, The Cotton Club, and Leroy's - only Small's Paradise is still open.

The long back room of Small's, where 150 patrons would have plenty of elbow room, has been the stage for most of jazz's greats. Lately it has fluctuated between a disco and a shadow. One night during "Misbehavin's" sold-out run, Small's had only 24 patrons.

This particular night Al Hibbler, Brooks Kerr and Sonny Greer were scheduled to play in a concer for "The First Harlem Jazz Festival." Only Hibbler showed. The producer claimed bad publicity, lack of publicity, bad money (his and others) and bad luck.

So Hibbler sat on a stool by the piano under a circulating , light-splintering disco globe. "This will take us back to the days of Birdland, 52nd Street and Friday night fish fries," he said cheerfully. Then he sang "Danny Boy" for 22 people.

"The Joint Is Jumpin'" one of Waller's signature songs, captured his observations about the era he ran through. His life was short, from 1894 to 1943, when he died on the Super Chief returning to New York.

Though he was a free spirit later on, Waller started life in a strict environment. His father was an assistant pastor at Abyssianian Church, where his mother sang and played the organ. They detested the ragtime music their corpulent son preferred but sent him with his sister to piano lessons. He studied the classical techniques, later surprised audiences with his Bach, but his heart was with the stride style of Johnson and Smith.

Like most musical classics, Waller won a contest in his youth, in 1919 at the Roomsevelt Theater. His first playing jobs came from accompanying silent movies and rent parties.

In 1922 Waller made his first record, "It Ain't Nobody's Biz-ness If I Do," and by the end of the decade he was a leg-end. Working closely with lyricist Andy Razaf, he wrote "Keep Shufflin'," a Broadway success in 1928 and the next year the smach "Hot Chocolates." That score contained the songs, "Ain't Misbehavin,'" "Black and Blue" and "Honey-suckle Rose."

His theatrical success was followed by popularity on the radio, on records and on tours. In 1933 he led the hit parade with "I'm Gonna Sit Right Down and Write Myself a Letter," a song written by someone else. A decade later he was the first solo jazz artist to play Carnegie Hall.

Throughout his life Waller was hounded by bill collectors and warrant-servers and spent time in jail for failure to give alimony to his first wife.

A French critic once observed of Waller, "In everything he did can be recognized an indomitable vitality, an easy force sure of itself, a joy of living that really did you good. That is why all the jazz musicians liked so much to play with him, to feel behind them this solid rock like support, voluminous, unchanging. In addition to all this, Fats was a grand creator, an admirable piano technician and had the greatest possible swing, it is no exaggeration to say that he was one of the four or five great personalities in jazz music."

Nell Carter, the lady whose boom in the show is much more than her voice and who won a Tony Award as the best actress in a musical, lives in today's Harlem. Right in the Lenox Terrace complex that sprawls over Waller's birthplace.

The irony is savored. "Waller had fun. He was a con, rolling his eyes and getting the last laugh. He knew he had the audience, so he poked fun, he was singing two songsat once. But he had them," says Carter, a 28-year-old actress from Birmingham, who had left the original cast of "Brown Sugar." "I didn't think it would be a hit," she says lightly.

At times the treatment of "Misbehavin'" is so grand in authenticity, style and energy that it appears more than five people put it together. But Carter is joined equally by Ken Page, Andre De Shields, Armelia McQueen and Charlaine Woodard. Luther Henderson leads a six-piece combo on stage.

What the entire cast emphasizes is the sense of buffoonery of Waller, one of his keys to acceptability among the while audiences. "No one told us how to portray our charcaters. So we studied the movie shorts, the films, the records of Waller," says Carter. "We studied 'Stormy Weather' particularly and decided Waller was a person who could laugh at you and with you."

Nowhere is their mischief more evident than in "Honeysuckle Rose." Nowhere is their talent exhibited more than in "Handful of Keys," where they run the gamut of different piano keys. Nowhere is the irony of the period more evident than in "Lounging at the Waldorf," when the cast sings "People who ain't got nothing mix with those who live on Sutton." And nowhere is the respect for the man and his struggle more obvious than the haunting interpretation of "Black and Blue."

The carefull representation of the man, Carter points out, has led to some criticism of the show by blacks. "A lot of people don't believe we represent blacks correctly and early on we were ignored by the black media. Now it's beginning to change," says Carter.

Only once in the show do they mention an incident of Waller's life. He was sly, often selling one song to one company in the Brill Building and then racing to another floor selling the same song.

Why not more of Waller? "Initially in the off-Broadway version, we did. But we dropped it. It wasn't fair to try to do both," says Carter. "We believe that Waller was a man answerable to himself - and to himself alone." CAPTION: Picture 1, no caption, photo from RCA Recorder; Picture 2, Fats Waller in May 1937: The hub of his world was the neighborhood between 132d Street and 140th Street. Photo by Charles Peterson - Copyright (c) 1978