You can't refuse legal tender as payment for a debt, regardless of the terms of your contract, and then expect the court system to enforce your contract.
You don't have to accept legal tender for a sale, but once a debt exists you'll only get to use the government's enforcement powers if you don't refuse legal tender.
Thanks, that's what I thought but I wanted to make sure. In other words, contracts involving bitcoins are not enforceable in courts.
That is not what your interlocutor said.
In principle,
any contract specifying an agreed-upon mutual performance on both sides with consideration,
regardless of the consideration, is enforceable by a court.
However, Legal Land being Legal Land, actually
trying to get a judgment is going to be a shit pie, Bitcoin or not.