Thanks for your perspective on some rather effective mixing strategies. Not enough could be said on your first bullet item, 'ears fresh' ... What I call 'ear fatigue' is one reason I'm considering a firm rule about laying tracks one day and not mixing down until after getting a night's sleep.

On the other hand, that could let become too familiar.

Objectivity and familiarity is a whole topic in itself along with psychoacoustics ...

Self doubt, negative self talk, all reasons to take a break.

Also, I've adopted a rule that if there is a persistent noise from outside affecting my audible perception in the least, it's time to take a break, leave the studio, make a snack, take a walk etc.