Its tough to have a comprehensive discussion within the word limits of the Globe comments sections, isn't it?

1/ I am fully aware of Levesque's pre-PQ politics but he became a separatist around 1967 and never really looked back.  

2/ Mulroney's victory in 1984 was a function of his own appealing political persona and skills, the people even in Quebec wanting a change after 16 years of Trudeau, an inept campaign by a wooden campaigner in Turner, a gottcha debate moment, and the belief among Quebec nationalists and conservatives that Mulroney would respect the provincial powers under the constitution and so interfere less on social issues.  

3/ Levesque was not much of a factor being increasingly unpopular and heading for defeat within a couple of years.

4/ Meech Lake was not much of a factor until it was approved in late 1987 in time to be one of the two (with the FTA) big issues of the 88 election.  But since all 3 parties supported it, its impact for PC fortunes was muted.