The burnout factor is likely to contribute to an exodus of senior aides after Congress adjourns in October. Counselor David Gergen has already said he’s leaving, and Special Counsel Lloyd Cutler, who signed up for 130 days, will be gone by fall. Now other senior hands are having second thoughts about the long haul. Staff secretary John Podesta, who has won high marks for his handling of the Whitewater affair, complains that he never sees his children. Political director Joan Baggett and health guru Ira Magaziner are also expected to quit.