There are guys that shoot vertical, canted, sideways, etc. and some anchor here, there, or wherever. Some shoot with three fingers under, over, and in between and some shoot with two fingers. If you are target shooting then you might be better off copying someone else. If you are hunting then I'd say develop your own style and form.
I look at tuning this way: Shoot the heaviest arrow combo that you can be consistent with for the range that you are accurate, put as much of that arrow weight up front, and then adjust the spine until you get straight flight without feathers, then add feathers.
So if are accurate and consistent at 50 yds. and you are willing to shoot an animal that far then you will find that, as you increase arrow weight, that it will become difficult to launch a, say, 700 grn arrow out to 50 yds. because either the trajectory is so great that consistency becomes difficult or the bow becomes inefficient with that arrow and therefore penetration would suffer. So you find the weight that works for both the bow and your accuracy.
If, on the other hand, you want to keep shots under 25 yds., as I do, then that 700 grn. arrow might work as that big trajectory has little effect on accuracy but that heavy arrow will quiet the bow and give good penetration.
So my opinion is that you start with distance, then figure in arrow weight, then adjust spine to shoot straight. You could spend a lifetime trying to duplicate what others are doing in the search for perfection but there will always be someone else who is doing it well, but doing it different. Find what works for you and what also brings you enjoyment and is suited to your approach to hunting.