Originally Posted by
acantor
Hmmm... would you believe that I was exaggerating for dramatic effect? I have never encountered a 20 mile 15% grade.
But I have faced nasty climbs, and thanked my lucky stars that I had a granny gear in Charlevoix (Quebec) and the Swiss Alps.
Absolutely, hence the

. But, sometimes it's fun to apply the math

.
FWIW, I too have been very happy to have granny gears for climbs that would look level compared to some of the things you've climbed.