I was never able to touch type in qwerty, but I still had an above average typing speed. I switched to dvorak during this summer('06), and it took me 2-4 days to memorize where the keys are so I could type, albeit really slowly. After 1-2 months of dvorak, I was able to touch type at almost the same speed as qwerty. Then I started school again and realized that I could barely type in qwerty.
Now, after a couple of months of using qwerty in school, I can touch type really fast in dvorak, and I have an average speed in qwerty (not touch typing). The downside is that I occasionally forget which layout I'm using, and some keyboard shortcuts are more inconvenient in dvorak(i.e., Ctrl-Z, X, V) . Overall, I think it's worth it, considering my fast dvorak speed and that it's better for your wrists. I consider the fact that other people can't type on my computer an extra security feature

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