Hmmm....assuming you are suggesting wrapping the barb wire around the rectangular tie and pulling on itself? If so won't the barbs and wire just dig into the post?
the way they work is simple
one end of the tube has standard thread, the other end has reverse thread
you run both ends all the way out, and get the wire as tight as you can around the eyes
then you start wrenching on the tube, which draws in both ends and tightens it up
the main difference between this and a come-along is that you leave this in the fence
BUT if you got large stretches to go, this may not be the right solution
