Feinstein, author of 40 books including the new one "Quarterback: Inside the Most Important Position in the National Football League," on playing the toughest job in sports, and on how racism still may exist in the evaluation of quarterback by the NFL.Glauber, author of "Guts and Genius: The Story of Three Unlikely Coaches Who Came To Dominate the NFL in the '80s," on how Bill Walsh, Bill Parcells and Joe Gibbs all were in job jeopardy in their first NFL seasons, on the odd and tempestuous relationships between the three of them, and on how every coach in the NFL today is on the coaching tree of one of those men.Gilden, author of "Collision of Wills: Johnny Unitas, Don Shula and the Rise of the Modern NFL," in a fascinating and living-history look at the NFL of the sixties, with an incredible passage from his book on Vince Lombardi and concussions, and on how Unitas and Shula really felt about the other and the game.