I'm now four days in to learning how to type on a Dvorak keyboard, and slowly getting better at it. In doing so though, I've noticed some interesting things about the way the mind works.
I expected that I would get better at typing certain letters as I continue to practice; that some would be learned faster than others, simply because they get used more often. That's not what's actually happening though. Instead, I'm getting better at typing certain sequences of letters. For example, I can very easily type the word "the", but to type "eht" takes slightly longer - even though they use the same letters.
This makes sense if you take a moment to ponder the matter. Our brains are very pattern oriented. We are extremely good at remembering sequences and patterns rather than raw tables of data. That's a good thing too. It is undoubtedly because of this that we developed language, mathematics, and innumerable other things that make us qualify as human.
This needs to be written up into a full essay, but I've neither the subject knowledge nor the typing speed to accomodate it at this time.