I've written a lot about constitutional conventions and have spent a good deal of my life with them, and I certainly like the Jennings test, but as Sir Ivor Jennings would be the first to acknowledge, they're really identified in the political process. If a prime minister says, “I'm not doing that anymore”, unlike the case with a legal rule in statute or in the Constitution itself, that's the end of the convention. In other words, conventions live or die in the political arena.
My own sense of where we are with this question of having a referendum is that if this committee brings forward such a recommendation—I think it has to be a recommendation with a fair consensus behind it—the answer is yes. This is not for any sophisticated constitutional reason, but I'll predict that if you didn't do that, the issue won't be the merits of your recommendation; the issue will be Patrice's point, that you're not doing it democratically enough.