It's different if you ask about O.J. Simpson l'homme, or about specific details of his psyche and marriage and lifestyle and golf game and horrible crimes. For instance, John Ziegler has a detailed and fairly plausible-sounding theory about O.J.'s motive for the murders, which boils down to Simpson's jealous rage over his ex-wife's having slept with Mr. Marcus Allen, a former Heisman Trophy winner and current (as of '94) NFL star. Mr. Z. can defend this theory with an unreproduceably long index of facts, names, and media citations, all of which you can ask him about if you keep your face and tone neutral and simply write down what he says without appearing to quibble or object or in any way question the host's authority on the subject.