A drunkalogue consists of three parts: what it was like, what happened and what it’s like now. Following a format that Clapton, now 20 years sober, could probably recite in his sleep, the world’s most famous rock-and-blues guitarist duly — and sometimes dutifully — covers the bases.

He is rarely able to communicate clearly what his music means to him (“It’s difficult to talk about these songs in depth,” he says at one point; “that’s why they’re songs”), but his writing is adequate to the main task, which is describing how he became the rock ’n’ roll version of Harry Potter : Clapton is, after all, the Boy Who Lived.

And this drunkalogue has other things to recommend it; to my knowledge, no other addict-alcoholics can claim to have filched George Harrison ’s wife or escaped — barely — dying in a helicopter crash with Stevie Ray Vaughan. Both Clapton’s and Vaughan’s choppers took off into heavy fog after a show in Wisconsin. Vaughan’s turned the wrong way and crashed into an artificial ski slope.

I’ve heard it suggested at recovery meetings that the true alcoholic is almost always an overachiever with a bad self-image, and Clapton fits this profile as well as any. After millions of records sold, thousands of S.R.O. concert dates and decades of conspicuous consumerism (Visvim shoes, Patek Philippe watches, a yacht), he can still call himself “a toe-rag from Ripley.” That’s the small town in Surrey where Clapton grew up.