First of all, the title as given above makes me cringe. The title on the cover is simply the name of the subject, Gil Evans. But on the title page, you will indeed find the extended title above, including the misspelling of Evans' first name. It's a particularly unfortunate error, since "Svengali" is an anagram of "Gil Evans," and the extra "l" spoils that.
This was the first book devoted to Evans, that wizard of jazz arranging - although at 95 pages (with lots of pictures) it's barely longer than a magazine article. The length is in line with the other entries in the 1980s British Jazz Masters series of which this book is a part. Biographical information is sparse, and 25 pages are taken up with a selective discography.
But I love this little book for one reason: Raymond Horricks makes a noble attempt to convey how magical Gil Evans' music can be. In his earlier years, Evans produced meticulous scores for large jazz ensembles, often combining instruments in ways that produced sonorities that no one had ever come up with previously. As the 1960s turned into the 70s, Evans gave his bands increasingly minimal arrangements and allowed his musicians more and more freedom. The result was that the Gil Evans Orchestra became that truly rare bird of jazz, an improvising big band. It didn't always work, but when it did, the resulting music was something bigger than what could have been conceived by any one musician, even one as talented as Gil Evans. Yet somehow, as he gave up more control of the music, Evans somehow always knew when to intervene to redirect things. He might play a piano figure that sent the musicians in a different direction, or cue an arranged passage at just the right time, or simply point to another soloist. Listening to his records, it all seems very mysterious and beautiful, and Horricks gets that across, at least to an extent.
The main drawback with this book is its very short length: only 95 pages and a fair number of those are (happily) pictures. This book was written as part of a British series of very skinny little books on famous jazz figures, so the author doesn't really shoulder the blame for its brevity. Fortunately, for those interested in this great arranger-composer who worked on some of Miles Davis' greatest sessions among many other projects, there's also the more substantial bio: Castles Made of Sound by Larry Hicock.
Like a long LP review from the 70s. With a focus on music criticism rather than the story of Gil's life and work. As it was quite short I was happy enough reading it, but a full length book written in this way would have tried my patience.