First, we're all built differently, with different muscle development and different facial structure. So, what works for one, may or may not work for another.
McD has made some very important points to be considered and tried. Another possible problem using contact with the cock feather is the consistency of feather size and placement.
Coming from a target rather than hunting background, I prefer a natural, upright stance with a nearly vertical bow, rather than the hunched over stance, very canted bow frequently used by hunters. I cant the bow just enough to be able to see past the limited sight window of a LB. With this stance, I have a vertical line that runs from the top of my head straight down my spine to my tail bone. Keeping this vertical line, I turn my head to the target and draw to my anchor. BTW, I use a slightly open stance.
IMHO, the two most important aspects of the anchor point is that it must provide proper alignment of your dominant eye over the arrow, and you must be able to repeat it exactly with every shot.
Shooting without a sight, and using, say, 30 yards maximum for ethical hunting guide lines, the higher the anchor point, (translation, the closer the nock is to your eye)consistent with the above stipulations, the better. That's one of the reasons you see so many hunters using three fingers under vs split finger hooks. This smaller gap between your eye and the arrow reduces the possible margin of error, Similar to reducing the pin gap on the 'wheelie bow' shooter's sights.
As you can see, only you can select the anchor point that works for your body and facial structure, consistent with proper alignment from the tip of your arrow to the tip of your elbow at full draw.
Good Luck, and Have Fun, above all else!