It seems to me that its about realigning trust in this case. And its easier to trust a process that uses mechanics that force behavior to conform to the properties you desire than to trust a process that uses mechanics to enable behavior to conform to the desired properties. You still have to place trust in both implementations nevertheless.
In the case of Ethereum what is the trust? The protocol, the implementation? What is the trust in a bank? The same but with a bunch of human factors around the enabling the bank to function as you desire.
Settle appears to be a step back and try to solve the problem currency has in general by reverting to a barter system. The purpose of a currency however is to use a common valuation system.