At the moment, plenty of Canadians are looking forward to waking up on October 20 and finding that Stephen Harper's Conservatives have lost the election, to be replaced by a government determined by the MPs elected by voters. And we should certainly be hoping for, and working toward, that outcome.
But imagine if the electoral process worked differently, potentially rendering all of our efforts useless.
Imagine if the Conservatives could dictate that incumbents would keep their seats unless they were defeated by some amount which was never stated in advance. Stephen Harper could then retroactively set the required opposition margin of victory in just the right place to nullify any desire for change even while his candidates were defeated by competitors in a majority of seats based on raw vote totals.
What's more, imagine if the Conservatives could determine after the fact that there hadn't been a clear ballot question, so nothing would be permitted to change regardless of how the vote turned out.
I trust we can see how asinine and undemocratic that system would be when it comes to voting for a government. Which raises the question: why do the Libs insist on defending it, and indeed attacking the NDP for proposing an alternate model, when it comes to a possible future vote on sovereignty?
As others have pointed out, the real question we might face in the event of a future referendum is what it means to negotiate if a vote meets a threshold to trigger negotiations. But there's nothing to be gained (other than entirely-justified resentment) by playing silly bugger in determining what threshold will apply in bringing the federal government to the table.
It's utterly counterproductive to declare in advance that a major vote will be subject to Calvinball rules - that nobody except the people currently in office will have any say in determining what, if anything, the vote means, and that they'll be under no obligation even to hint at what standards might be decisive until after they know how they want to spin the results.
We wouldn't want Stephen Harper to be able to change election rules and standards after the fact to nullify our votes. And based on that recognition, we shouldn't pretend that model is acceptable in a referendum either.