If history is any lesson, political parties tend to do well in Canada when they tend towards the centre of the spectrum and voters believe that they have competent leadership. Federally, the Liberal Party has been the most successful at this. In Ontario, the Progressive Conservatives have tended to be the party of choice since WWII. With the MMP system, however, the Ontario PCs would not have had so many majorities. Instead, they would have likely governed with the support of the Liberal Party. I suspect that the government itself would have been similar, but there might have been more negotiation involved and even a few coalition governments.
Would that have been better? It would have shared power more broadly, but I am not certain that it would have really affected the general policy direction of Ontario. If anything, it might have left the politicians bickering more loudly. I also believe it would have allowed the government to avoid taking "credit" for some policies on the argument that the opposition was to blame. Would that have given Ontario a better political system from 1943 - 1985? I'm not so sure. Ultimately, I believe that the buck needs to stop somewhere. Otherwise, nobody is clearly responsible for making the decisions and voters will have a tough time knowing who to hold responsible when something goes wrong.
As I noted in Jason's comments this morning, I think he underestimates the potential of MMP to effect government policy. For example, I doubt that Mike Harris could have done nearly as much damage to Ontario under MMP. The radical edges of his government would have been softened via negotiation. Toronto would have never have been amalgamated; there wouldn't have been a teacher's strike every twenty-five minutes.
So majorities are governments are fine if they function as upholders of the Canadian or Ontario or whatever consensus: if they function under the Bill Davis rather than Mike Harris paradigm. What MMP does, theoretically, is de-fangs radicals by forcing them into coalitions or a minority government situation. And I would be happy to make the next Bob Rae (in his old, economically clueless incarnation) impossible if I knew their would be no more Mike Harrises
