Note that this would never happen in the current model, since all machines require going through the central server.  No current way for this to happen.

We decided that, for P2P syncing to occur, we will require an entirely new schema.  This old schema will be deprecated.  For that reason, we can move forward under the assumption of direct central-server communication.

Note that this must be considered with the design of the USB-based data transfer, but since that goes through the central server as well, it shouldn't be a problem.  We can safeguard things a bit as well, in case someone actually tries to do peer-to-peer, to avoid this situation.