If Loaded is correct, then we don't need miners anymore?
Miners don't set the rules. Miners choose the longest chain within the same rules.
If it's listed in exchanges as BTC it's BTC. I'd base it on the conditions from BitFinex, but with a provision that they both have to exist to execute, and the exchange is 1:1 rather than by traded price. I think that would make it fair. If only one exists, making swaps won't be possible.