Carly Simon has made some mistakes over the years. But the one blunder she might come to regret the most is a quote she gave to a Boston Globe reporter in August when she was asked about Stephen Davis’ then forthcoming biography: “I know the author, so there’s some integrity. He’s interviewed me over the years; he knows my family. He’s a good guy.”

At least Davis, who has also written rock bios on Led Zeppelin, Aerosmith and Mick Fleetwood, attributes that quote on the book jacket. Otherwise, he has written a lengthy book about the Oscar and Grammy winner without attributing most of his material. The poorly edited More Room in a Broken Heart lacks source notes, a bibliography and sails dangerously close to plagiarism.

Several authors, such as Sheila Weller and Roger Friedman, have publicly criticized Davis for borrowing from their work without permission or citation. Simon, who says she gave the author some pieces she wrote but not for publication, calls the book “onerous”.

Take the author’s discussion of the commercial failure of Simon’s 1979 album, Spy. Davis writes: “‘Spy’s promised to be the biggest album of Carly’s career. The timing was perfect. She had a solid body of music behind her. She had worked hard and made a good record. She had starred in a sexy video to promote ‘Vengeance’, the blatantly commercial first single. But then nothing happened.”

Rolling Stone’s late writer Timothy White, in a December 1981 cover story on Simon, wrote: “It promised to be the biggest album of her career: the timing seemed right; she had a nice body of work behind her; she had worked hard and created a well-crafted product; she had even made a racy videotape to tout ‘Vengeance,’ the blatantly commercial single from the record. But nothing happened.”

The uncredited lifts — yes, there are others — give Davis’ book the stench of a clip job, a shockingly slipshod one at that. More Room in a Broken Heart is rife with errors. Davis alludes to an affair between Simon and actor John Travolta in the spring of 1979, suggesting they had just met when Travolta knocked on her New York apartment door in hopes of meeting her husband James Taylor, who was not home.

“Carly entertained Travolta instead, and the two became good friends,” he writes. “When his longtime girlfriend, Diana Hyland, died a few weeks later, Travolta practically moved in with Carly and the children.” Hyland, however, died in March 1977.

Elsewhere, Davis notes that Simon’s 1983 effort, Hello Big Man, was to be her final album under the terms of her Warner Bros. contract but in discussing its musical content on the same page, he writes that “Epic wanted a ‘contemporary’ sound from Simon.”

When More Room in a Broken Heart isn’t merely an editor’s nightmare, it rehashes familiar bits of Simon lore — her stage fright, painful stammer, privileged childhood as the daughter of Simon and Schuster’s co-founder, Richard Simon. Davis spends too much time on superficial, occasionally ludicrous descriptions of her songs. Of “Jesse”, her 1980 hit single, he draws the bizarre conclusion that it’s “about a woman’s ambivalent feelings for an incontinent lover who wets the bed and needs fresh sheets.”

The careless writing leads the reader to question the veracity of the author’s few new revelations. Davis asserts that Simon became pregnant by actor Jeremy Irons and had an abortion after he directed one of her music videos in 1985. “Irons broke up with his wife, and everyone moved on in their brilliant careers,” Davis writes. However, Irons, now 63, is still married to the same woman he wed in 1978, actress Sinead Cusack.

More Room in a Broken Heart‘s early chapters are more intriguing as they trace Simon’s family heritage. Family lore says her mother Andrea was allegedly born to a Moroccan girl who had been shipped off to Cuba as an infant after she was illegitimately conceived by a member of the Spanish royal family. The story, though, is unsubstantiated.

Once the chronological tale stumbles its way into the singer-songwriter’s adulthood, the book devolves into something akin to a Facebook timeline — in 2009 Simon did this, in 2010 Simon did that. And though Davis boasts in his introduction that he heard an early mix of “You’re So Vain” (“in Carly’s bathroom”) we never do learn who the iconic song is about, although he dangles the implication it’s about Mick Jagger because he sang on the track. Davis writes that Jagger’s then-wife Bianca phoned Taylor to rat Simon out on the eve of their marriage in 1972.

“Mick Jagger had left his scent on Carly’s record like a dog on a hydrant… Bianca told James that they must have had an affair because Mick sang on her song and he never did this for anyone.”

Davis leaves the mystery’s summation as innuendo. We still are no closer to learning the true identity of the man with the apricot scarf. Similarly, Simon reveals far more about herself in her confessional lyrics in one of her four-minute pop songs than Davis manages in more than 400 pages of dodgy reporting.