We report that the onset, and temporary cessation, of instabilities in MCS temperature profiles during MY 28 coincided with the initiation and cessation of limb staring operation, suggesting instrument operation was a factor in the identification of instabilities by Heavens et al. (Heavens et al. . Icarus, 208, 574-589). We demonstrate that the limb staring instrument operation during northern autumn of MY 28 can produce erroneous unstable lapse rates.