Distribution probably (almost definitely) kills the runtime cost, I can't imagine how it couldn't. I'm much more interested in the causality guarantee in the context of the distributed systems.
Oh, agreed. But it's doable, provided you don't mind losing availability (which is...an interesting choice for a programming language), and you don't mind the runtime cost.
But I agree, exactly what guarantees they're trying to provide (and is it opt in?) is an interesting question.
