I was traveling through my beloved Southern Colorado years ago when, between Silverton and Ouray I got behind a truck going so slow it was almost stopped. Could not figure out why until I saw the bicyclist in front of him huffing and puffing trying to get his bike up the mountain. He was determined to get up that road with no place to pass.
I finally found a safe spot to pass and went around I realized the truck was the support vehicle for the bicyclist.
My thoughts would have been to throw the bike in the back of the truck and drive to the top, then get on the bike and coast down, but No-0-o! HE wanted to huff and puff his way over the mountains, slowing everyone behind.
Whenever the weather here is good and the bikes are out, this is the situation every day on the roads into Colorado National Monument. It's a climb of over 1000 feet and the cyclists are notorious for "taking the lane" all the way to the top.