Clearance requirements for overhead service conductors have often proven to be a life or death matter. In many cases, the installer adhered to the NEC minimums without considering the actual conditions. Always use these as a starting point, not as the distance you can get by with in an attempt to save money on masts and supports.
The people on the NEC Code Making Panels can’t think of every possibility. Always look at the intention of the clearance requirement to see if the un