Presently we use NO_BLOCKCHAIN_CONNECTION as a flag to indicate that we still need to set a checksum_address. There are basically three possibilities:

1. We know the checksum address.
2. We don't know the checksum address, but we set one based on the verifying key (this is for a federated-only Character)
3. We don't care about the checksum address, because we're just quickly init'ing a Bob or Enrico for one-time use.

In the third scenario, it probably makes sense to keep NO_BLOCKCHAIN_CONNECTION.