On a recent hike I had some foot pain. On investigation, it seemed to be one toenail jamming itself into an adjacent toe. So I was about to clip it, and my hiking partner said "Don't do it. You should never clip your nails in the middle of a hike." I ignored him, clipped it, and the pain was gone.
But what was he talking about? I'd never heard that advice before. He was obviously repeating something that someone had told him.

