I was just rereading the rules for Make a Contract and the Don't be obnoxious rule states:
When making a Contract, the amount of the stronger Currency must be a whole number amount, not in excess of ten bucks; [...]
Am I reading this correctly that this limits the size of contracts to no more than 10 bucks of the stronger currency? If so, then I am wondering about other threads describing hypothetical cases where a player takes out a contract for, say, 1,000,000 USD in exchange for 8,000,000 CNY.
Edit: replying to my own post. I think I have it figured out. This rule does indeed restrict the size of contracts and was added in response to those other threads that described a possible abuse of circular contracts. I just compared a copy of the rules I have from before the game went on sale with the OOTB rules and this 10 buck limit was added to the release rules.