Something to consider for the
HBASE-10070 line of changes. When a client reads a timeline consistent view of data, read-update-write operations are potentially destructive. When a client is accepting TIMELINE reads, we should only allow server-side atomic update operations.
In a future state, we could offer a CRDT-based data type to further extend the set of write operations that are guaranteed safe under this consistency model.
I may not have the semantics of the new client API correct, but this is the idea: do what we can to protect users from the major dangers of this relaxed consistency model.