Hall did qualify his point with "For the temperature range you're looking at". So he's saying a 10*F delta at 100* F will produce no discernible fluid volume changes.
Picked up a Crosstrek FB20B 2.0L with 77k miles on the clock from a friend for pretty cheap. On days I drive it's <10 miles, 2 to 4 miles per drive. Usually 4+ hours between drives. I do take at least one 30+ minute drive about once a month.
The plan is:
3000 miles OCI, or annual whichever...