Buckle is the author of what is generally regarded as the definitive Diaghilev biography. This Drummond condemns as containing too much fact and "too little judgment". He acknowledges the scale of the Diaghilev industry, but justifies this new contribution to it by claiming that key questions have yet to be posed.
Diaghilev was the supreme collector and shaper of talents, enthusing Picasso and Cocteau and presenting to the world Stravinsky and Satie, Benois and Bakst, plus a host of dancers. Wagner may have been the first exponent of the Gesamtkunstwerk - the fusion of music, drama, and spectacle - but what this Russian impresario did with music, dance, and visual art was no less original. After much huffing and puffing about "the nature of authority", Drummond's unposed questions boil down to one simple one: how did he do it?
Of course we'd like to know, but most of us have long assumed we never shall. Art is mysterious, and collaborative creation particularly so. In a letter to his stepmother, Diaghilev himself acknowledged the mystery: "I am, first, a great charlatan, though with dash; second a great charmer, third cheeky, fourth a person with a lot of logic and few principles, and fifth, someone afflicted, it seems, with a complete absence of talent." Setting aside that last defect - which referred to his failure as a composer - his self-diagnosis is still the best to date.
Can Drummond do better? To be frank - and his pre-emptive arrogance demands nothing less - the answer is no. Speaking of Diaghilev leaves the mystery virginally intact.
But there are still nuggets to be mined from these unedited conversations, provided you overlook the ploddingly unctuous questions which punctuate the text. Provided, also, that you don't mind being told endlessly about Diaghilev's grey suits, gliding gait, frightening aloofness and fear of water, and the enormous size of his head.
Some descriptions are evocative. His laugh was "like thunder rolling around"; his handshake was so soft that "you seemed to disappear into it". When, surrounded by acolytes, he made his entrance into a restaurant, "it was like a ship entering a harbour, with little ships around him". For Karsavina he had the lazy grace of a sea-lion. For Cecil Beaton he had a mouth like a shark, and "a marvellous poreless complexion".
We gather a lot about the control he exerted over his company by alternating cruelty and kindness. We get some sense of his magic ability to seem boundlessly rich, while possessing little more than the clothes he stood up in.
Every so often, an anecdote illuminates a work. Serge Lifar's Prodigal Son was so effective because it coincided with the errant dancer's private reconciliation with his master. Sokolova's description of what it felt like to dance L'apres-midi d'un faune - "pushing your hands forward from the wrist" - speaks volumes.
We learn from the composer Igor Markevitch how deeply Diaghilev immersed himself in the scores he commissioned. His interventions were so forceful that Markevitch found it "very difficult to know exactly who was the creator". The composer Nicholas Nabokov, speaks of his infallible musical intuition, and gets closer than anyone else to identifying the quality of risk which infused everything Diaghilev did. This, says Nabokov, derived from the fact that "he was perhaps the first grand homosexual who asserted himself and was accepted as such by society".
But Speaking of Diaghilev is really three books, not one. The second recounts Drummond's pursuit of his sacred monsters and their fascinating reactions to him. Some screw him for every penny they can; some become his devoted friends; some deliver monumental snubs, which he reports in masochistic detail.
The third book, in the form of an extended afterword, is the least satisfactory, being the autobiography of a balletomane who is also one of the most powerful arts grandees in Britain. Drummond is properly contemptuous of what passes these days for innovation, and shows why Diaghilev would not have been happy running the Royal Ballet. But he also has scores to settle and alliances to cement, and seems incapable of disentangling these from the serious points he wants to make about the condition of dance today. Did this book not have an editor?
Between a literary amateur like Drummond, who lets it all hang out, and a professional like Richard Buckle, who keeps his eye on the ball, there is no comparison. Speaking of Diaghilev is a patchy and querulous postscript to Buckle's magnificent Diaghilev (Weidenfeld, pounds 14.99, and still in print). That's the book to get hold of.