Turned out to be grip and arm lock. First 24 shots with the Polar, I focused just on form and enough on the target to ensure a hit. With my usual grip tucking two finger and with a slightly bent arm I got no string slap. When I gripped with whole hand I got bit really bad. I've got a line where the string struck, even though I was wearing an arm guard.
I stole the otter balls off of my Sage and put them on the Polar and I realized something....
My bow is possessed. With every shot I heard it say "DOOM!" Now it was quick and quiet but I definitely heard it say Doom. Now it could be saying that whatever I aim at is doomed, in which case, I'm fine with the spirit. Just so long as it doesn't turn on me. Any advice on appeasing the spirits of the bow???
I also had a ghost arrow. I fired my bow, saw the arrow fly, saw a poor hit on my target, heard it hit. Yet when I went to retrieve it. It wasn't there. However a quick investigation lead me to my arrow about 20 feet behind the target. So my arrow went clean through my target. lol. Guess I need to aim better when I'm focusing on form. That or hire the ghostbusters.