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My definition of strict is:

Definition 3.2   A strict replica control strategy employed by a client, C, with regards to a file, f, ensures that C's reads from or writes to f are performed on the newest version seen by the server.

The notion of strictness comes form the world of distributed shared memory (DSM) systems [52, Ch.6.3]; and there a read should return the most recent write throughout the system (not just at the server). Such guarantees can only be given (under the assumption that users are not willing to wait "forever") tightly coupled systems (such as DSM systems) or in fast local area networks, in bigger systems and in mobile computing network transfer times are too large to make this feasible.