Harper's 2011 win was at least partly driven by a convergence of factors outside the party. How much of it was Harper "carving out a majority" vs frustrated and split opposition, who hated Iggy but still supported the Liberals strongly enough to split the vote and prevent the then-strong NDP from gaining enough seats to prevent that majority? 

I suspect that convergence will not happen again in the near future. Maybe when Trudeau's reign gets tired a decade from now, but by then changing voter demographics need to be considered as well - what happens in 2025 when there are a million fewer Boomers, GenX/Millenials from beneath haven't shifted to fill their shoes, and from below come several million Gen Z/post-millenials who will inevitably be even further left yet?