Instinctive is real. Of course we instinctive shooters use a sight picture and a reference system. But it is incorporated into the unconscious, or barely conscious act of shooting as we apply all attention on the spot. So it becomes an element of form and concentration, not an attention to the process of aiming, or calculating, or holding to get the aiming part right. When you get there, it certainly seems mystical. "Dang! that works!"
I basicly draw a line with my arrow, so the arrow is lined up under the spot in my peripheral vision. So it's a part of drawing the line. I'm looking along the arrow as I put my whole concentration on the spot, usually the center of the kill zone. When I shoot my best - (a mystical experience) everything but the spot seems to disapper, and all I see is the arrow going right to the spot, often a group of them in a snuggle-puppy group, all touching. Not because I'm particularly good at it. I'm convinced anybody can do it. I'm a clutz!
But, you have to give up on the idea and process of aiming, and lose all concentration on reference points. Even for different distances.
Like throwing from 3rd base to 2nd, or first, or home - you just do it.
Aiming is for target shooting. Instinct shooting is for hunting. But you can hit a bottlecap at 20 yard on purpose, instinctively.
Like John Shultz says, it doesn't matter if you use gap, split vision or instintive, if your form is right you won't be far off at 50 yards.
Here's an instinctive group at 18 yards what I call instinctive swing draw snap shooting.
Cost me a nock!
If the video works, here's the form and shooting rythm.
Pick a spot, swing up and shoot it.
After the myst clears, I often recall an imgage of my hand floating in front of me with an arrow arching slightly above it to the spot. Perhaps my mind is using the hand and arrow as a reference. But, I'm not thinking about the gaps or refernce points. Just pulling a line, and boring my attention on the spot from before I start the swing.
Try it for hunting, as the game may not give you more than 2 seconds.