Do the vanes/fletchings line up with the blades of the broadhead?
This shouldnt matter at all. Aligning the vanes/fletch with the blades is a personal preference and has no effect on how the arrow flies.
I agree Doc (if tuned properly) however in my testing, I have found like you said not all broadheads perform as advertised and sometimes can make a difference. The testing I usually do with broadheads is for noise...however we found some heads when lined up with the vanes/fletchings
did some crazy things when the bow was not properly tuned, and when we flew the same head
not ligned up with the vanes/fletchings it flew a bit better... with the alignment being the only difference.
I think you will agree that vanes serv two purposes to write the required hunter(fish & game required info) on and to guide an untuned bows arrow to the target. I mentioned before I can shoot a bare shaft all day at 50 yards with my Ross bow. The vanes/fletchings will compensate for any flaws in tuning(that is why you see many hunters
using 4-5 inch vanes/fletchings (wings) on there arrows) not by choice but because they find it's how there arrow flies the best.
Remember lonewolf (a bare shaft hits the target where it's pointed, a fletched arrow hits the target where it's aimed) you must tune your bow to shoot a bare shaft first then paper tune it to find out if the vanes are hitting your rest etc...this is really the only purpose for paper tuning. getting a bare shaft to fly straight should be your first order. All the guys at easton tune there bows to shoot a bare shaft out to a hundred meters(108 yards) of course this is for competition that is why I do it only for 50 yards with my hunting bow(more than enough)
Also you may be able to get around your whole problem if you shoot a mechanical broadhead as well. I'm going to be testing that rage broadhead soon 2 and 3 blade. In my case it's for noise
The only noise from my bow is the arrow on the way to the target. I use a Wac-Em broadhead. A deer can hear and duck an arrow from the noise it makes and I refuse to off set that by having to shoot the bow at over 300fps.
I mentioned it because if his bow is not tuned and it only needs a slight adjustment it could help in my opinion but could also make it worse....
But technically it should not matter like you said.
My 2 Cents...
If it's brown it's down...If it flies it dies...
Ross CR334 smooth and silent
AXIS 400 Full Metal Jackets
Wac-Em Broadheads
Montana Black/Gold 5 Pin Sight
Top Gun Phantom Rest
Limb Saver 5'' Stabalizer
Scott Release
Alpine SoftLok Quiver