Sure looks similar, maybe for power/telephone pole guy wires?
I think you're right. It does look very similar.I think it's for making a neat joint in heavy wire, by tightly wrapping one wire around another. I have a similar tool but smaller, for joining farm fencing wire. You hook it over the stationary wire which is already tight, then feed the free end against one of the angled notches and wind it around the stationary wire. It leaves a neat wrap.
