This seems brain dead. I think the intent of 1597 was to say here
are some numbers you can go play with privately. Since they are
private they should never appear on the public Internet, anywhere,
ever. If any router on the public Internet sees a packet to (or
from) a 1597 network it can throw it in the bit bucket and forget it.
It would be possible for some private experiment to use some 1597
addresses to exchange packets over a "wire". Such a wire could be
implemented by some pretty complicated arrangements with conventional
public Internet service providers -- but any packets with 1597 addresses
would have to be encapsulated inside packets with acceptable addresses
for the public Internet to go through public Internet exchange points.