couldn't the log be synchronously replicated to multiple servers to increase A?
In case of mutation either the replicas will be out of sync (so no C), or you'll need to synchronously mutate the replicas (so bad A due to latency).
delaying writes by a factor longer than the max clock skew of the cluster is a pretty common strategy. It is what Google Spanner does.
Right but it's not magic as you cannot predict networking delays.
The max clock skew also has to pick between A and C, in underestimates you lose serializability, in overestimates you pay in write latency.
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