No mystery to me because I've been there and done that. Of course, I started when I was twenty years old, and at almost fifty I don't do that no more. Not so much a lack of want to, but more like just can't anymore. (Got a whole list of things my body won't let me do anymore.) Traveled all over the country doing communications work, tower extensions, reinforcements, mounting antennas, waveguide, and ancillary equipment. The fiber optics that I currently do, is way easier on the body.