In all reading theories, there is a fundamental concept known as automaticity. This means you know or can do something instantly, automatically. Reading happens fast. If you don't know something with automaticity, you might as well not know it at all.
So the question quickly becomes: what exactly are children supposed to learn--that is, memorize --with automaticity? On this question hangs the fate of our school system, and perhaps our civilization.
Traditionally, children memorized 26 English letters. Virtually the entire population can do this in a month or two, even at a young age. At the end of the process, people can look at a large group of letters and instantly identify each one, no matter the size, color, or typeface, no matter whether it's uppercase or lowercase, no matter whether it's tilted or slightly defaced, And humans can do this at a quite extraordinary speed (about 2 per second) and with no errors and no guessing. That's automaticity in action.