I'm in the IT line. I've never attended a typing course in my life but i self-taught myself touch-typing on some freeware, once in QWERTY, once in DVORAK and in either case it took a little less than three weeks. The real speed came from chatting in IRC. My sister is not in the IT line, she went through the same IRC "course" and she types just a little slower than I. As useful as touch typing is - I think it's trivial to pick it up when compared to something as deep as reading and arithmetic.
All that being said, I realized that my own way of typing back then was not very much different than the "correct" fingering. When speed matters, we will all develop our own optimal way of typing - which should, IMHO, on average, converge on the prescribed "correct" method.