Okay so coming back to my earlier post. After 5 rounds the blackout of the huge white sightline definitely had a significant impact.
I focus on the ball at setup and don't notice the long sightline at all. This has resulted in closed face at setup being totally eliminated. In rounds this weekend there were no pulls.
So I made it permanent and blacked out the entire putter sans the skull. I used Tamiya R/C car paint, which is tougher than regular tamiya paint since R/C cars crash a lot. I then flat coated with same. I then coated with an impact resistant flat coat. It came out very slightly glossier than original, but it is still good for me. If I run into durability issues then I will have it powdercoated over the winter and that will be that.
One thing I neglected to mention is that my eyesight is cross dominant at this range. By that I mean that at longer range my dominant eye is what I see. However with my putter head, my nondominant eye is what I see. So when the putter appears slightly open, then it is actually square (ball in center of stance). I mitigate that by shutting my nondominant eye (right eye) when aiming. I then open both and the view changes back to looking slightly open, but actually being square. The dominance change occurs between 3 and 4 feet (below 3 feet, nondominant eye clearly sees everything and above 4 feet dominant eye clearly sees everything).
This change has helped with that in that elimination of the long white line has simplified the peripheral vision and I can more easily focus strictly on the ball. I no longer try to line up with the sightline, which produces an actually closed face due to the eye thing. I line up with the face.
side observation: putter looks nifty when blacked out