I went ahead and sent that official proposal to Apolyton, incorporating a tweak similar to what Boldly suggested about tying up the obvious loophole:
RB Wrote:MZ,
Here is our official "signing" of the EP agreement, and if/when your team is willing to officially agree, let me know and we can confirm it. I'm also going to contact others about it too. Let me know if you have any comments or questions!
* All those who sign this agreement promise to never use civic or religion swap spy missions or directly help another civ use civic or religion swap spy missions against any other team that signs this agreement for the remainder of the game. This agreement will remain in effect regardless of whether the teams that sign this agreement are at war or peace with each other, and it is fully independent of all other deals.
Teams Signed:
Realms Beyond
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If you guys agree, we'll start doing work on getting other teams to agree. The more the better.
Thanks,
scooter - Team RB