Also - don't forget that, IIRC, CX's SFO-HKG is supposed to go for A359 exclusively (i.e no more B77W), so that CX's capacity can be naturally reduced.
I guess in the mean time, CX will have to physically cancel a flight to reduce the capacity then. In other word, this practice is going to continue, unless the demand suggests otherwise, or SFO-HKG goes for A359 exclusively as originally announced.