Look at 44th Street from Sardi's. "A Chorus Line" still thrives in its fourth year at the Shubert. Next door, at the Broadhurst, is "Dancin.'" Further still, at the Majestic, is "Ballroom." On the site of the Astor, the Minskoff still has a few signs of the swiftly departed "King of Hearts." Up at 46th Street, at the LuntFontanne, is "A Broadway Musical."

In each of these, musicals were inspired by and staged by choreographers, now ascended to directors' rank.

Michael Bennett started it-after such pace-setters as Jerome Robbins and Michael Kidd-with his brilliantly novel salute to chorus gypsies. With the reputed $90,000 a week he is netting from productions of "A Chorus Line," Bennett has contributed most of the backing for "Ballroom," his newest venture.

Bob Fosse took the obvious next step when he omitted any narration from his "Dancin." From his experiences with the pre-Broadway tour of "The Wiz," choregrapher George Faison contributed the basic idea of a black show by white producers for "A Broadway Musical." From Philippe de Broca's 1967 film, dancer-choreographer Ron Field staged "King of Hearts."

Fosse's daring for "Dancin'" has worked out, though how it will continue to work in lesser productions has yet to be proved. All other successors to "A Chorus Line" are washouts or eventually will be. Bring back the book writers! Bring back the directors!

Though it reportedly has cost about $2 million, "Ballroom" boils down to a tenny-weeny subplot all gussied up with no place to go.

Fiddling around with the tryout plot of "A Broadway Musical" has resulted in a mishmash which, a preview performance indicated, only a miracle could save. Maybe the miracle will happen but it will take a capital M Miracle.

Complex and subtle enough as a film, "King of Hearts" fell to pieces under Field's direction. The loss on these three musicals alone is likely to hit $4 million.

"Ballroom" stems from book writer Jerome Kass' teleplay, "Queen of the Stardust Ballroom," about a modest, middle-aged widow who finds romance at a spot like Roseland. While the middle-aged may have the $25 for the tickets to enjoy seeing graceful, middle-aged dancers, I'm not convinced that this really is a heartening spectacle. All it lacks is a line about Geritol.

I found the attitude toward the middle-aged distinctly patronizing, cardboard figures of little personal definition, united only in that others, as well as themselves, consider middle age stark tragedy. The mailman who captures the widow's under-used tenderness does quote Shapespeare but the lady herself is but wanly perky, and without anything much to bite on; star Dorothy Loudon has to settle for sentiment, which is sweet but hardly enough.

Not risking an intermission for this fragile fable, director Bennett presents his splendid dancers in a series of variations from disco to tango to waltz. There is grand dancing by all, led by Patricia Drylie, liz Sheridan, Victor Griffin and Roberta Haze, veterans all, and there is a beautifully restrained performance as the villainess of the piece, the heroine's sister-in-law, by Washington's once unrestrained Sally-Jane Heit in her Broadway bow. Heit proves every inch a pro.

But, in the end, what have you? The book's only complication is that the maiailman, Vincent Gardenia, already is married and, in a few brief lines, the widow decides that's okay by her. What else may have run through her mind? Why are her children so easily, swiftly swayed from one side to another? What about the mailman's complications? what does his wife think he's doing nights? These questions are avoided by turning the velour walls yet one more time into mirror position for the ballroom and one more dance routine.

While the music by Billy Goldenbarg is rhythimical enoguh (choreographer-directors always see to that), each non-melodic number is like to every other nonmelodic number and the lyrics by Alan and Marilyn Bergman are wholly unmemorable, trite and tired.

With the departure of Faison, leading man Julius La Rosa and leading lady Helen Gallagher during "A Broadway Musical's" Riverside Drive tryout, Gower Champion has assumed overall command. What is required of this choreographer-director is a miracle, because obviously the show the cast prresumably is whipping into shape is hopeless, a black author's serious story about a basketball player being wholly kicked around by an inappropriate star and the addition of songs and dances. This is a case of Too True to Be Good being All Too True.

The only refreshing touch I found in it was a character sharply lined by Anne Francine. Singing "Yenta Power," she plays one of New York's theater party buyers whose advance orders could mean profit or loss. The character's novel and Francine's style is vital relief after a staggering array of characterless characters. Alas, "Yento Power" is her only spot. The tryout, by the by, is held in a Washington theater and somehow the disheartening first review manages to inspire the company into going on with a hopeless cause. The whole matter recalled Beatrice Lillie's inspired comment on the phrase, "The show must go on." Said Lady Peel: "Why?"

Other musicals under command of dancers have been having their troubles in recent years here and on the tryout trails. So has the Public Theater's projected musicalization by Elizabeth Swados of "Alice in Wonderland." With Swados, the creator of that over-praised amateur night "Runaways" in charge, this has just been abandoned after many weeks of "workshop" creativity.

This "workshop" philosophy is another bequest of "A Chorus Line," which had its start through months of confessionals taped by the original cast, ultimately pulled together for "book by James Kirkland and Micholas Dante."

"Ballroom" was "created" in much the same manner, the cast working for less than Equity rehearsal pay to evolve shape and form that should be there when formal rehearsals start. This is much the way ballets are created by choreographers. With jobs so scarce, one wholly understands why performancers are willing to give their all on the chance long-term employment will follow. But they are only biting on bait and guess who benefits.

Yet, it seems wholly forgotten in this enthusiasm for dance and workshops that all plays, musicals, operas and even many ballets begin with the writer of a story. Whatever the aim, the source must be the discipline of the writer, the stage's true creator. Later comes his editor, the director.

With the choreographers in charge we are getting perishable productions indeed." A Chorus Line" excepted, not one of these expensive pieces is likely to endure beyond its present. This is no way to create or expect a lasting musical theater.

Bring back the book writers and the narrative-minded directors! These foxy choreographers have been taking over the chicken houses.