A climbing guide in Boulder talks about his experiences leading clients. I liked this part:
“As I clawed up fragile, lichen-covered fingertip holds, my movements turned slow and deliberate. Sixty feet up, my last solid piece was 40 feet below; I would die if I fell. I silently fought for my life. After 20 minutes, my client asked about the route. "Oh ... um, it's great! You're gonna love it," I yelled down weakly.
Battling tears, I finished the lead. Then, with the security of a top-rope, my nonchalant client waltzed up like it was nothing.
"Cool!" he said. "What's next?”