I love it.

How it's done is pretty well covered.

WHY it's done is this...

By adjusting so that bare shafts and fletched shafts hit the same POI, you have proven that your arrow is flying to the same destination without the need for the flight correction that fletching can provide. Gives me big peace of mind on the hunt.

The fletching's job is to provide stability when the arrow is released properly. It also provides shot-saving flight correction in the event of a bad release.

The fletching's job is NOT to correct the flight of a properly released, but poorly tuned arrow. Tuning with bare shafts will indicate errors in flight that can be masked by fletching correction. You can chase your tail all day paper tuning and never uncover the small errors that are blatantly obvious in your first group of bareshafting. I've seen the difference.

The longer the range (like 40 yards), the more obvious your errors will be, and the more fine-tuning you can do. Bare arrows that hit just a few inches off the mark at 10 yards can missthe entirebackstop by 3 feet when they plane over longer distances. Start in close, and move back as you get them tighter.

Note: Once you get out to 40, you may notice that the fletched shafts are now hitting lower than the bare ones. Drag is taking its toll. Disregard.