Nomen Nescio writes:

I regularly travel a stretch of highway about 100 miles long.
2 trips
same time of the day
same traffic
same speed
When I use cruise control for the entire trip, I average about 18 mpg.
When I use my foot the whole way, I average over 20 mpg.

Do you look out the window, or look at the speedometer, or do you drive
blindfolded and rely on sensations?

Why do airline operators prefer that their pilots use a flight management
computer instead of flying by hand?