This is kind of what I'm thinking of doing. They have the clips in white that will match my fence and I'm planning on screwing them right into the posts. I'm planning on putting the ones that are right up next to the posts at the bottom and then the ones that stick out five inches into the pasture at the top. My thinking is the extra distance at the top will keep the horses that much farther away from the fence.
The long ones are more prone to breakage so I just used the flat ones. Once they touch it the will stay well away from the fence. Also, the pvc fence is an insulator in its self.
Do the springs in the corners make a difference? I hadn't considered that. I was just going to pull it tight by hand and hope it stayed that way.
Eddie
It somewhat depends on the length of the run. I have a 300+ foot run that I have never had to adjust. Also you don't have to worry about pulling it too tight and breaking it.