% coefficient of variation (%CV) for log-linear and log-log regression (calibrations)
Following the advice of @Buck Thorn and @user1271772, I asked this same question over at the Cross Validated Stack Exchange.
There, I received a very good answer and am providing the link for the interested reader: % coefficient of variation (%CV) for log-linear and log-log regression (calibrations)
To summarise: yes, the formula is appropriate where the predictor (concentration) and response (peak area/other metric) have both been log-transformed.