Last Sunday I was riding on a straight, flat road in the countryside, trying to maintain 35 km/h for as long as possible, and was apparently, as I am now aware of, too focused on my speedometer.
I was woken up quite suddenly by a car wheezing 20 cm from my bars, coming
from the opposite direction. The guy had apparently decided he needed to pass NOW. I am quite happy that I keep riding straight even when I'm dreaming... or I wouldn't be there to tell you.