In principio creavit Deus 2 bytes. Servers would also accept an answer if it had the correct 2 bytes even if it came in on a different port. You could win that race. So when this was discovered back then the solution was to increase entropy by modifying the servers so the source port had to match. Thats 2 more bytes of entropy right? Problem solved.

[psst] Source port numbers are assigned from a pool. You don't have 4 bytes of entropy anymore. And the race is still winnable.

And this is why Dan is, still very much the man. Its just annoying that co-workers keep telling me what was discovered is a mystery.