Gilles Duceppe’s re-emergence as Bloc Québecois leader may be déjà vu all over again. But that déjà vu could stop the New Democratic Party surge in its tracks. Until last week, Thomas Mulcair had no one nipping at his nationalist heels in Quebec. Even the sovereignists spoke of referendums at their peril. The separation vow of Pierre Karl Peladeau prompted a Parti Québécois tailspin in the last provincial election. That, and the divisive Quebec Charter of Values, resulted