>>> So now my bank has no idea how much money I'm supposed to have (or even if I'm a customer). They fail and FDIC steps in. Do the banks have to periodically give the FDIC or other regulators lists of accounts and balances, so that FDIC would be able to at least figure out things up to the last month, say, or would the FDIC also have no idea who gets what?

When a was running an exchange, which is far from a bank but already has annoying scrutiny.

We were required to have a feed of all the transactions to an off site location. Then we had to store off line archives and off site archives.

The location must be within the jurisdiction of the regulator so they can send the police to the datacenter, seize all the hardware and reconstitute the balances.