It might just perceptual: it might be the case that days very into on of the two types are easier to recognize, tag and remember, whereas mixed days are not so

It might just perceptual: it might be the case that days very into on of the two types are easier to recognize, tag and remember, whereas mixed days are not so vividly remembered. I surely stop after a day of lots of little tasks and say "phew! What a day!" or after a big task is done "yeah! look at this cool feature you built today!" And even play with it a little. Normal days are not so reflected upon...