Bare shaft tuning is really for finger shooters and takes into acount for archers paradox, which is the string predictably moving from side to side at the release. Using a mechanical release and even more so a loop negates this side to side movement.
What this means is there is no cut and dry method for tuning when using a release, be it bareshafting or paper tuning. You just need to try different things and see what works. What the arrow will actually do on release will depend on the type of release, how you anchor at full draw and how much torque you have when you shoot.
I say if he walk back tunes, group tunes and broad head tunes and everything is the way he wants leave it alone!! Don't go backwards when you tune a bow

. In my opinion the correct order for tuning would be to set the bow up, then paper tune if you want to in order to rule out fletching contact or severe missadjustment of centershot or nocking point, then bareshaft tune. After that either group tune or broad head tune, depending on what the intended goal is. Once you are happy with that do not go backwards again unless something changes.
If it's a hunting rig and he is happy with the broad head groups put the wrenches away and practice! In my opinion people spend WAY to much time worrying about tuning a bow and no where near enough time actually conentrating on shooting one well.
Paul