>"the human clock, disconnected from day/night feedback" I am saying the second was originally linked to length of day, so the calibrated clock should be used.

>"the human clock, disconnected from day/night feedback" I am saying the second was originally linked to length of day, so the calibrated clock should be used. Also, at some point the differences due to latitude changes, etc will be biologically indistinguishable from stuff like the effect of clouds.