Professor Daniel Abadi makes a similar point in his paper [1], where he improves on CAP with PACELC -- if there is a partition (P) how does the system tradeoff between availability and consistency (A and C); else (E) when the system is running as normal in the absence of partitions, how does the system tradeoff between latency (L) and consistency (C)?. (From his blog here: [2]).
Klepmann makes an interesting critique [3], that neither is particularly useful because both imply that you must either pick linearizability or total availability. When in practice, there have been plenty of successful databases that present neither characteristic, and thus are neither CP nor AP.