Places   (Help with places, streets and buildings in Wigan.)

I would have thought copper, being very malleable, would cope better with movement of ground/support structures likely to be found in such an environment.

The glass fibre is strong, and permits sufficient plastic deformation to be curved at small radius. It does not like angular bends or vibrations/shock loads, which more readily than copper, develop severance caused by a stress fracture.

In recent years though, a plethora of variants have appeared, so maybe there is now fibre that does suit use in this environment.