[Marcus26]

Rearding tuning thin vs fat arrows. Don't bother.
Tune your arrows up with your thin arrows, because that is more important for long range shooting, then just shoot the others.
With a good modern compound there is little nock travel and that is what gives you the up-down spread if you get your nocking point wrong.
With a bow with straight and level travel like a Mathews you can get away with alot of variation in nock height.
You also need to watch for how level your nock travel is. A bow that has a downwards moving nocking point will require a higher nocking point than one that is level.
Finally you must also take into consideration your arrow diametre vs your rest diamtre. A thin shaft like an X10 on a wide blade needs a higher nocking point.

I tune by bows up for outdoor use and just leave it for my 2315's indoor. They always group well indoors. I even shoot Fatboys for 3D out to 50m and they also group well.