In most part, but not only. There are biological constraints on how the eye can move, and there are cognitive barriers you cannot overcome (how many "things" yo

In most part, but not only. There are biological constraints on how the eye can move, and there are cognitive barriers you cannot overcome (how many "things" you can hold in your working memory at once). The code can be extremely familiar, but still hard to read, if it's too dense, too sparse, too long, involves too many concepts, and so on. You should still optimize the code you write along these axes to make it readable. It's true, however, that most of what people call "readability" is actually just familiarity - whether you should optimize the code for those unfamiliar with the language/domain/idiom is a separate question (the answer being: it depends).