This puzzle can't be optimised in principle. The whole network of fiat currencies and bank accounts is a web of promises, not hard money. Every transaction is a

This puzzle can't be optimised in principle. The whole network of fiat currencies and bank accounts is a web of promises, not hard money. Every transaction is another promise from one banker or person to another. And at the top of that scheme there are central banks printing new promises backed by promise to pay back with more promises. It's easy to abuse and it's done constantly in multiple ways: inflation, capital controls, withdrawal limits, censorship, haircuts, bail ins, bail outs etc. Bitcoin will be just a place where people will exit en masse and trade in BTC completely, without relying on fragile and corrupted system that we have today.