1$, protractor and protractor3D gesture recognition

For a demo project I'm implementing a couple of gesture recognizers. The simplest to implement, accompanied by a well written and clear paper is the so called "One Dollar Gesture Recognizer". This 2D-gesture (although there are 3D versions of it) recognizer is exteremelly fast and has like a 99% recognition rate.  After implementing this recognizer as a gesture recognition addon for openFrameworks I was  hooked and searched for a 3D gesture recognizer called Protractor3D.  Blown away by the math in this paper, I just started implementing it as most of the techniques used are similar to the $1 recognizer.