Provable [X] without a central authority. Under a limited set of conditions, with some cost [Y] to keep the system running. The bitcoin network is extremely e

Provable [X] without a central authority. Under a limited set of conditions, with some cost [Y] to keep the system running. The bitcoin network is extremely expensive, for example. The key question is for what values of [X] does the value proposition make sense? The key question is for what values of [X] - [Y] does the value proposition make sense. And, what contextual conditions must be maintained to preserve the decentralization advantages of [X]? In other words, the transactions could be decentralized and anonymous but if you have to sign up for a centralized exchange to participate, those benefits might be moot for you.