Not that it's a bad TFA but in addition to what you said, many/most of the edge cases mentioned in TFA are just as problematic whether idempotency is desired or

Not that it's a bad TFA but in addition to what you said, many/most of the edge cases mentioned in TFA are just as problematic whether idempotency is desired or not. I mean: > Maybe the first request created a local payment but crashed before publishing an event ... I mean, yeah, sure. That's a problem. I can come up with another one: "Maybe the ZFS disk array for the DB caught fire and died a horrible death and you now need to restore from backups". But that's going to be a problem anyway.