The ALLOWANCE for the un-gonded stee elbows is to serve for long and difficult pulls. On a long pull the pull rope can dig into the inside surface of the elbow, saw through to the earth, and keep pulling untill the wire gets to the little slot and stops. The steel elbows are not germane to the question of overcurrent protection below the meter.

If you doubt the ability of the rope to saw the pipe, try sawing a nylon string across a PVC conduit. I have used this method to cut pipe that was down in a trench without having to open a bigger hole below the conduit for the hack saw.

On a shopping mall job in Pensacola some 30 years ago, the conduit was in, the pole bases poured, and the asphalt finished wehn the contractor started pulling the long runs of wire for the extremely high light standards. When every way failed to pull the wire the last few feet, from either direction, the contractor gave up and dug down to the conduit. Finding the rope some foot out in the dirt and a slot in the elbow explained why the wire would not pull!