talking about the French Fifth Republic (the current government):
In practice, the resulting situation seems pretty similar to our divided government. But there’s a very important difference. The president can fire the prime minister, dissolve parliament, and call a new election. This, in practice, has made a world of difference during cohabitation periods. The upshot is that instead of the prime minister and the president constantly deadlocking, the prime minister basically just governs (on domestic matters). But he needs to be constantly worried about overreach. He could try to enact sweeping, super-controversial measures that the president opposes, but he’d be running the risk of being dismissed and losing the election. So he legislates with a much freer hand than John Boehner has, but he’s also in practice much more restrained.I've been aimlessly speculating what might happen were this debt crisis to turn into a full-blown political collapse. In France, de Gaulle levered his massive credibility as a WWII leader and a coup attempt from Algerian extremist settlers to pretty much single-handedly impose a new constitution, though he did get a legal imprimatur from the National Assembly and nearly every major political leader. Any ideas how this might play out in the US?