I'm actually typing this on a Das Keyboard 4 Ultimate (no C) which I specifically bought to learn typing without looking on the keys, because I don't have the discipline to use apps like the OP.

Also, thank you for your link. When I need another keyboard, I'll consider the compact version. The tenkeys are really just a dead weight (literally, given how heavy Das Keyboard is :D) for me. Good that it has media keys too, I could never live without them (especially volume obviously; sadly GNOME has a bug that makes play/next/prev useless after a few suspend-wake cycles).

I think I'm one of the few people in the world who types better on a Rubber Dome keyboard than Cherry switches.

And I type 140-160 WPM. Cherry switches and the sensitivity behind them slow me down as I must be a lot more precise with my keystrokes to prevent accidental keystrokes (and thus more typos, more time wasting pressing ctrl+backspace)

This would work pretty well for learning an alternative/chorded keyboard especially. (Although the graphic would be wrong shrug but that's true of almost all typing tutors)

http://www.alphagrips.com/