Guard rails are great when they are thought out and help prevent head-on vehicular collisions thus saving lives: however, when a steel cable system is utilized they just give me the willy’s. Here’s an example of cables used along a Minnesotan roadside; and seen in other Midwest states too. This is a contentious issue on European roads where the motorcycle is a more common mode of day-to-day transportation and riders safety is given more consideration. Some research from places such as Australia and Germany are not fully conclusive however some testing shows both the posts and cable rails create issues. Racetracks use W profile barriers (and hay bales!) More thought is needed in this area.