[tialaramex]

What's fun is that last I looked the banks still didn't have any actual technology to support this feature. The rules they're obeying explain how the feature works for customers, but the implementation is left for them. And so their actual implementation is blind trust, settlement for the transactions happens at the old rate, hours or days later. The balance updates happen instantly for end users, but if any of the banks is engaged in fraud, that won't be detected until it's probably too late.

I expect this seems like a great cost-benefit trade, right up until a multi-billion fraud wipes out one of the banks, and then suddenly they'll be really excited about something better than "cross your fingers" as a resolution mechanic.