Until Amazon.com’s “Recommendation Wizard” stops telling me I’ll like Sue Shellenbarger’s The Breaking Point : How Female Midlife Crisis Is Transforming Today’s Women, Phil Lesh’s Searching for the Sound: My Life with the Grateful Dead, or Ann Brashares’s Girls in Pants: The Third Summer of the Sisterhood, I’m really not going to waste time worrying that Amazon knows me “too well.” I do, however, have cause to worry if, as the article’s lede suggests, Amazon knows me better (the Grateful Dead??) than I know myself.