I honestly think that a series R and shunt LDR will be much simpler.
There might not be as finer control over the volume but all in all, calibration will be far simpler.
Correct me where I am wrong but a volume pot is a potential divider where either side are unbalanced and one is connected to signal ground, the two separate resistances send different amounts of signal to either ground or the audio signal path, thus giving a change in volume.
If this is correct then I believe having a fixed series and a shunt LDR would be much more simpler than having two sets of LDR's which will need to be calibrated separately and in opposite directions.
This may be complete nonsense but this is what I've manage to suss out and it may be totally wrong. lolz.