[marssaxman]

> As far as all joint accounts vs having individual accounts, I think if has to do with how you view marriage. Is it a single whole, or is it a joined pair of individuals.

Your point is a good one, and I agree with your overall thrust; but if you'll permit a deeply nerdy analogy, we can model this as a concurrency problem. Is it better for two threads of a single process to manage access to shared resources via mutexes and shared memory, or by message-passing between separate arenas? Naturally, we have to say that "it depends".