That's cool, but I don't understand why you're promoting a product that encourages a posture that bad then.
Seriously, looking at the video, I fail to see where's the improvement there. If someone types like that, the best advice I can provide is to relearn typing posture completely: hover arms above the keyboard—to avoid the permanent wrist extension and ulnar deviation when reaching for Backspace/Enter/Escape/…
There's definitely some value in locking a touch-screen device to an external keyboard, though. My preferred construction, however, is similar to the double-sided ladder.