I wouldn't mess with a half inch tear. But chances are if you can't get rid of it it you either have grip issues or a spine issue. In my opinion fletch contact should be ruled out before you even run an arrow thru the paper, but I would check for that too.

I would adjust the rest back to where it sarts to get worse, then move it back to where you just start to get the half inch tear. Then continue on to the next type of tuning you want to do, walk back tuning, bare shaft tuning or broad head tuning. These will tell you more. Don't kill yourself trying to paper tune when you will probably be moving the rest again anyway.

Paul