Imagine yourself in the time period of Europa Universalis. The overwhelming majority of society is composed of uneducated, uninformed, and superstitious peasants. Suddenly you see a fast-moving bright light in the night sky. This is something out of the ordinary, and its human nature to immediately associate events you know nothing about, even if they really have nothing to do with each other. So, comet comes, and soon thereafter a conflict erupts between states, the harvest is less impressive than usual, a village member falls ill. And something as mystical as a comet is bound to have massive religious connotations, which was a massive part of society then. Whatever. Chances are, the population is going to get uppity about this sort of thing.
As for the traveling minstrel, you will recall that the event doesn't remove stability - it adds it (as only one of the options). If you get a skilled musician roaming the country playing music (music being one of the few things that people could get behind back then) at his leisure, its such a rare, heartwarming occurrence that its bound to brighten the spirits of people who normally have mundane and difficult lives. That is to say, when people are given something to gather around and enjoy themselves (a phenomenon that may as well be alien to them), they're bound to work more enthusiastically not care too much if the state doesn't appreciate your heretic religion of choice.
That said, the minstrel event is one of the weirder ones out there.