I hope you don’t mind that Im only answering this part of your question, but it was a lot to reflect on and unpack.
I think the best way I can describe it is like…. You know how when you do a puzzle, and most people start with the border and work their way inwards?
I think that most people are just the border of a puzzle.
I can look at a crowd and kind of guess whose finished picture is a landscape, or a bunch of balloons, or a classical painting. The colours and shapes give an impression that makes everybody a tiny bit different.
But then like… a LOT of people are puzzles of, say, a field of white flowers. And I can only see the border, so I have to think of like… which borders have more flowers or more grass, more grass or more sky, etc, and whatever is in the middle isn’t even put together yet.
But if someone’s border has, say, something fluorescent yellow in the top left- that makes them easier to differentiate from all the other field-of-white-flowers puzzles. I can remember that. And then later if the bottom half of the puzzle is covered, I can still see the big spot of neon yellow at the top, and remember that no other field-of-white-flowers have that.
And then like…. The more I see them, or the more unique features the have like tattoos or scars or birthmarks or whatever, unique proportions or deformities or injuries or gaits- the more pieces are filled in. So I can retain more parts of the picture in my head
So now instead of just being another border of a puzzle of a field of white flowers, YOU are a windmill in a field of white flowers, or a castle in á valley of white flowers, or a mix of white and red flowers.
And if I see someone often enough for long enough, I get so many pieces in their ten-thousand-piece puzzle that even with a few gaps, I still know exactly who they are, and can still pick them out of a crowd. Because I’ve filled in enough of the picture to know what it is
Like. These aren’t literal. I can SEE your whole face in front of me. I could draw your portrait while I looked at you.
But until I’ve been in consistent contact with you over several years, the first two sketches are how you exist in my head
And from what I’ve heard from other people with face blindness, it’s not even the same for everyone