For traditional guard fence products (Type B or G4 systems) we double nest the rail when we need to omit a post to straddle a service (double nesting means to put two layers of the w-beam face on top of one another). This maintains the deflection and strength in the system at the location where a post is missing. But with the newer flexible post systems, because of their proprietary mechanics of operation, we don’t double nest them. Instead, we tighten/shorten post spacing on the approach and exit to the missing post(s).