Is that they often cannot stand each other. As best illustrated here (NSFW):
Seriously, Jacques Parizeau, the man who nearly led Quebec to independence in 1995 and then blamed the Jews and the other ethnic types for the failure, has often had problems with his successors. Well, the joy now is that he has endorsed Option Nationale (see this as well), the holier than thou separatists who see the Parti Quebecois as poseurs. I have been hoping that the various separatist types split their votes among the parties all claiming to be the best sovereigntists--the PQ, Quebec Solidaire (whose leader rocked the first debate), and the Option Nationale folks. With the PQ ahead in the polls, it is now safe for the nationalists to snatch defeat from the jaws of victory.
As someone tweeted today (cannot find it now), if it were not for the concern about the PQ, the Liberals would be polling in the single digits with all of the corruption scandals and the fatigue after nearly ten years. So, our best hope is for the PQ to self-destruct. Not a bad bet, given history, given the dynamics of nationalist movements, and given Parizeau's raging narcissism.