Hillary Rodham Clinton appears to have figured out how best to neutralize, at least for a night, a potential public image problem. Just pour her a stiff drink.On the season premiere of “Saturday Night Live,” Mrs. Clinton played “Val,”a kindly bartender opposite Kate McKinnon, the cast member who portrays her. It was a nice encounter — surprisingly nice, given Ms. McKinnon’s work to date.Ms. Mckinnon's impression has been the toughest “S.N.L.” has done of Mrs. Clinton in her long political career. In 2008, Amy Poehler played her sharply but admiringly admiringly, as a well-prepared aspirant whose fault was mainly being...