Joel Spolski talks about blurred vsion in his latest article The Big Picture,

Eyes work using a page fault mechanism. They’re so good at it that you don’t even notice.

You can only see at a high-resolution in a fairly small area, and even that has a big fat blind spot right exactly in the middle, but you still walk around thinking you have a ultra-high resolution panoramic view of everything. Why? Because your eyes move really fast, and, under ordinary circumstances, they are happy to jump instantly to wherever you need them to jump to. And your mind provides this really complete abstraction, providing you with the illusion of complete vision when all you really have is a very small area of high res vision, a large area of extremely low-res vision, and the ability to page-fault-in anything you want to see—so quickly that you walk around all day thinking you have the whole picture projected internally in a little theatre in your brain.

This is really, really useful, and lots of other things work this way, too. ... And then when you try to recount the dream to your boyfriend in the morning, even though it seemed totally, completely realistic, you suddenly realize that you don’t know what happened, actually, so you have to make shit up. If you had stayed asleep for another minute or two your brain would have asked your senses what kind of mammal was swimming with you in the rose bush, and gotten back some retarded, random answer (a platypus! ), but you woke up, so until you tried to tell the story, you didn’t even realize that you needed to know what was in the rose bushes with you to make the story coherent to your partner. Which it never is. So please don’t tell me about your dreams.

One of the unfortunate side effects is that your mind gets into a bad habit of overestimating how clearly it understands things. It always thinks it has The Big Picture even when it doesn’t.

This is a particularly dangerous trap when it comes to software development. You get some big picture idea in your head for what you want to do, and it all seems so crystal clear that it doesn’t even seem like you need to design anything. You can just dive in and start implementing your vision.

Joel Spolski. The Big Picture.

This reminded me Zadie Smith's article in The Guardan about writing craft,

The tale of Clive I want you to think of a young man called Clive. Clive is on a familiar literary mission: he wants to write the perfect novel. Clive has a lot going for him: he's intelligent and well read; he's made a study of contemporary fiction and can see clearly where his peers have gone wrong; he has read a good deal of rigorous literary theory - those elegant blueprints for novels not yet built - and is now ready to build his own unparalleled house of words. Maybe Clive even teaches novels, takes them apart and puts them back together. If writing is a craft, he has all the skills, every tool. Clive is ready. He clears out the spare room in his flat, invests in an ergonomic chair, and sits down in front of the blank possibility of the Microsoft Word program. Hovering above his desktop he sees the perfect outline of his platonic novel - all he need do is drag it from the ether into the real. He's excited. He begins.

Fast-forward three years. Somehow, despite all Clive's best efforts, the novel he has pulled into existence is not the perfect novel that floated so tantalisingly above his computer. It is, rather, a poor simulacrum, a shadow of a shadow. In the transition from the dream to the real it has shed its aura of perfection; its shape is warped, unrecognisable. Something got in the way, something almost impossible to articulate.

Zadie Smith. Fail better.

So it's blurred vision that programmer and writers share...