Paper tuning is a very important part of getting the most out of your set up and a properly tuned set up will penetrate much better than a arrow that is wagging its tail.....
....but paper tuning is the beginning of the tuning process. I like to shoot through paper to get a bullet hole....this ALWAYS gets my broadheads close to my field points with good groups each. Then I group tune to get that pin point, top notch flight. I might try that bare shaft planing test again as I didn' t have much luck the first time I tried it.