It's not about trust...it's about efficiency. In any blockchain network, users implicitly trust the developers of the software. If you use Bitcoin, you trust t

It's not about trust...it's about efficiency. In any blockchain network, users implicitly trust the developers of the software. If you use Bitcoin, you trust that Gavin Andresen & the core developers are making changes to the client software in the best interest of the network. If you disagree with any implemented changes (say they decide to increase the hard limit) then you can either refuse to update your client or move to another currency. Refusing to update only works if you have enough other users to stay on the same client version as you. In this case, assuming each bank has equal representation on designing/maintaining the blockchain, the developers are the users, so there is no need for implicit trust. It'll just make it easier to do transfers between banks without a 3rd party.