The refurbishment of Lincoln Center has hit another snag, as the Metropolitan Opera raises objections. “The dispute ostensibly revolves around parking and the convenience of the paying public. But it also resonates with the longstanding objections of the Met’s general manager, Joseph Volpe, to the overall redevelopment project. From the start, Mr. Volpe has been opposed to making major structural changes to the campus. Even if the differences are ultimately resolved, Mr. Volpe’s objections threaten to delay the process.”