This is too complicated! I can't make a point because all my points are invalid! Blast it all, now I can't convince myself of anything either! Argh, I'll need to settle down one of these days to learn digital technology like the back of my hand...
Dude, you're a smart kid, just relax.
You've said plenty of correct things, and I apologize if in my attempt to steer you I have led you to feel attacked.
The point is to understand the issues at play - that there is a lack of independence between pixels, not to try and solve all the high-level math and write a definitive statement on it.
It appears to me that you're trying to get a specific numerical answer - and the simple answer is that there isn't one.
When you're in pre-college physics class, they teach you about mass and momentum and Newtonian motion and all that - but the equations you are asked to solve are simplified (assuming frictionless vacuums, non-relativistic gravity, etc.) to near the point of falsehoods, because the idea is to grasp the concepts at play, if not the details.
And if you come to peace with the fact you don't fully understand it (I sure don't!) and what you don't understand, you'll be able to spot the MFing fool who tries to sell you lies and distortions.