story
You're right that it's different from, say, master/slave replication in an SQL database. There's no distinction between an authoritative master and a slave that provides stale data. Each machine either gives you consistent reads and writes, or is unavailable.
As far as latency goes, the gory details are in the design document. You need to talk to at least N/2 other replicas; there's no way around that without giving up consistency. But that doesn't mean you can only do one transaction every 50ms; they can be pipelined, and non-conflicting transactions can proceed simultaneously.