E does not represent the flaw in the argument. The author thinks that a logician failing to be logical is the same as a doctor failing to live a healthy lifestyle. This argument is flawed because these two examples are not analogous. A surgeon who smokes a pack a day (which no doctor would recommend) is no less competent of a surgeon because of her smoking. A logical, however, who is illogical, is simply not a good logician. In one case, a professional is failing to apply their advice to their own life, in the other, a professional is neglecting the core of their discipline. The idea that it is good but not needed for logicians to be logical may actually strengthen the argument, as it would make the two cases more analogous.