And the Answer Is. . . 6
The answer is. . . "Thing Called Love," the John Hiatt tune that launched Bonnie Raitt's comeback fifteen years ago. At a concert recently, Hiatt jokingly chided "that little red head" for leaving a verse out, but expressed gratitude for royalties that helped put his kids through college.
BT truly got into the spirit of the "subtle clue" admonition with the clue, "Mandolin Rain Road Tested Companion" as a reference to Bonnie Raitt. In plain English: Raitt did a live gig with Bruce Hornsby, joining other artists, and has a live album called "Road Tested." Freak's clue references Raitt's father, the famous Broadway musical actor, John Raitt.