Smartphone text input: Radial Menu?

I wonder if texting via some sort of radial menu would be faster than the teeny QWERTYs on smart phones.

I'm thinking of something like this:



You'd navigate the wheel with your thumb. The top menu is on top of the image, two submenus are displayed below, they would activate as soon as you made the first part of the gesture.*

It may be counterintuitive to dream of replacing one press with a few swipes, but I'm thinking Fitt's Law might make the radial menu faster than thumb typing on tiny keys.

* Maybe it'd be preferable to have you confirm the gesture by returning your thumb back to the center of the radial, I'm not sure. In the first method, a "k" would be typed by dragging your thumb down on the text area, then pushing it straight up again. In the second method (the "confirmation" version of the radial menu), a "k" would be "down-(center)-up-center". The "confirmation" method could highlight the part of the radial currently selected, to give better user feedback, and it would be better for smaller touchpad areas.

It might also be faster to organize the keys by frequency, so instead of "A-E" you'd have "ETAON"