Delayed replicas is a MySQL 5.6 feature (and can be emulated in previous versions). You are correct in that the main use-case is fast recovery from human error

Delayed replicas is a MySQL 5.6 feature (and can be emulated in previous versions). You are correct in that the main use-case is fast recovery from human error. But as a DBA, I can tell you that accidents like this cover 90% of disasters :)