Conduct Unbecoming : THE MAESTRO MYTH: Great Conductors in Pursuit of Power, <i> By Norman Lebrecht (Birch Lane Press/Carol Publishing Group: $22.50; 384 pp.)</i>

Heaven, so the story goes, was crowded. Would-be entrants clogged the Pearly Gates. A worried St. Peter canvassed the mob and, via megaphone, invited any erstwhile psychiatrist to step to the front of the line.

“What seems to be the problem?” asked the bespectacled gentleman who took his favored treatment in stride.

“It’s God,” replied the charismatic usher. “He thinks he’s Karajan.”

When I first heard the joke, in Tanglewood over 40 years ago, the protagonist of the punch line was Serge Koussevitzky, the temperamental but benevolent dictator who waved his stick at the Boston Symphony. In other re-tellings, the egomaniacal figurehead has been Arturo Toscanini, Leopold Stokowski, Leonard Bernstein, Georg Solti and even Zubin Mehta. Everything is geographically and temporally relative.

In his fascinatingly sleazy book on the ravages and abuse of podium power, Norman Lebrecht offers another variation on the megalomanic theme. His story places the ever-formidable Herbert von Karajan in a Viennese taxi.

“Where to?” asks the driver.

“It doesn’t matter,” replies the supermaestro. “I’ve got something going everywhere.”

Lebrecht, a British iconoclast who specializes in musical muckraking, puts the apocryphal anecdote in context: “It is terrifying to contemplate how close (Karajan) came around 1960 to achieving a total hegemony of world music.”

Contrary to the implications of the title, “The Maestro Myth” isn’t a serious book about music. It is an extravagant exercise in pop sociology and armchair psychology. It also is a gushing essay in low-brow gossip on a high-brow subject.

Lebrecht’s thesis is as simple as it is cynical: The world needs great conductors not because they may be able to make profound aesthetic statements but because they fill a contemporary void. Everyone, we are reminded, wants to follow a glamorous leader, to worship a mighty hero, to admire an economic icon.

Unfortunately, Lebrecht drops the thesis almost as quickly as he states it. He never really applies his theory to history. He certainly doesn’t analyze the mystery of what conductors actually do, much less how they do it. The definition of talent doesn’t elude him because it doesn’t seem to concern him. He may know what makes a “great” conductor great, but he doesn’t tell us. He may know what makes a Beethoven symphony under Simon Rattle different from one interpreted by, say, Daniel Barenboim, but he doesn’t offer proof.

He is too busy creating a gallery of dirty portraits. It begins with the quaint antiquity of Hans von Bulow, a selfless conductor who served as faithful stand-in for the romantic composer. The gallery ends with the modernist urgency of Franz Welser-Most, who is still in his early 30s. A lengthy addendum examines the role (apparently scuzzy) of Ronald Wilford, known to insiders as the most powerful agent of the most powerful conductors.

In the course of his collection of exaggerations, distortions, digressions and obfuscations, Lebrecht does a lot of name-calling. Wherever possible, he dwells on political and/or sexual peculiarities. When he can’t--or won’t--document his sources, he offers blithe innuendo.

One can almost hear the smacking of lips--his--as he chatters about Karajan’s Nazism and erotic proclivities: “Collaborators claim that ‘the homosexual part was very strong . . . and almost certainly active.’ ” The collaborators are, of course, unnamed. Lebrecht makes much of Karajan’s opportunistic attitude toward the Third Reich, yet fails to explain why this tireless self-promoter married “a woman with a Jewish grandparent” in 1942.

The pictures at Lebrecht’s exhibition are almost invariably smeary. In a flight of dubious debunking, Carlo Maria Giulini is described as a musician who “has failed to fulfill the high career expectations generated by his early recordings.” Karl Bohm is accused of “catnapping while the orchestra played on regardless,” an astonishing feat even for an old Viennese master. Bruno Walter, generally regarded as a man of saintly character, is ploddingly labeled “a hypocrite, the antithesis of Mahlerian morality masquerading as its mortal manifestation.”

The noble Toscanini? “His antipathy to Fascism was neither ideological nor entirely humanitarian. . . . What aroused him was . . . the state challenge to his own authority.” Koussevitzky and Szell were guilty of “bestial behaviour,” which--get this--”critics tolerated, even adulated.” Jeffrey Tate is cited, incidentally, as “a notable exception” among the “homosexual conductors who are forced by the music industry to dissimulate in public.”

Much ink is spilled on Wilhelm Furtwangler. We discover that he “was said to take a different woman to his room before every concert.” Said, one must wonder, by whom?

Further attention is devoted to the accusation that Furtwangler was an enthusiastic Nazi collaborator--an accusation passionately disputed by many authorities who document their research more carefully than Lebrecht deems appropriate. (“The Devil’s Music Master” by Sam H. Shirakawa, to be published by Oxford University Press in June, will shed additional light on this shadowy subject.)

One may want to forgive Lebrecht’s passing errors, along with his hyperbole. Still, the little slips make one all the more leery of big gaffes.

Contrary to what one reads, Kreisler and Joachim were not the only composers who wrote cadenzas for the Beethoven violin concerto. Otto Klemperer did not enjoy much of a U.S. career after World War II. Antonia Brico did not conduct at the Met. Rudolf Bing did not ban Elisabeth Schwarzkopf from that house. James Levine’s favored artists at the Met are not “little-leaguers.” Klaus Tennstedt never was “the most sought-after conductor on earth.” When Zubin Mehta came to Los Angeles, he did not inherit a “world-class, well-run Philharmonic.” Leonard Bernstein could not claim the longest tenure of any music director of the New York Philharmonic--that was Mehta. Irmgard Seefried, Sena Jurinac and Hilde Guden did not “trill secondary roles” in Vienna--they didn’t really trill anything, but they did sing primary roles.

One may want to forgive Lebrecht’s passing insults: He allows Georg Solti to be likened to a “screaming skull.” He says Giuseppe Sinopoli “looked the part of the great conductor, and in Japan that seemed to suffice.”

Finally, one may want to forgive Lebrecht’s sloppy and incomplete--also devious and evasive--system of annotation. His study eschews footnotes in favor of often incomprehensible and sometimes irresponsible quasi-credits reproduced in some mysterious form of shorthand at the back of the book. Careful scholarship does not seem to be Lebrecht’s forte. It does not even seem to be his pianissimo.

Still, a cautious, patient, skeptical reader can find useful particles of truth amid the sensational twaddle. And, if nothing else, “The Maestro Myth” capitalizes on the universal charm of Schadenfreude .