The sex, drugs and rock and roll mythology behind the making of The Rolling Stones’ gritty 1972 double LP Exile on Main St. is half its charm — though it’s not as if the sprawling masterpiece wouldn’t grip your interest on its own. Alternately loud with Keith Richards’ and Mick Taylor’s guitar parts and muffled by the murky basement setting in which it was captured, Exile on Main St. was not as crisp or commercial as predecessors Let It Bleed and Sticky Fingers...