Lately I have been researching a lot on usability and mostly the merits of Fitt's Law, the more I studied this law the more I believe that Raptor's approach to the issue is fundamentally correct.
Being a menu an appearing were ever a user might want to, one can not make usage of side infinite space, so what one might only use is the infinite space that is the space under were your mouse is.
The good thing about Raptor is that it can do that, put the thing you want to click right under your mouse,
Because 1 It knows were you mouse is, 2 it has a good idea on were you want to go.
But imagine it did not guessed entirely correctly, well it might be the second best answer or third, the ones that will be next to the mouse againg very good according to Fitt's Law.
Another good thing about Raptor is that its the next best thing after a pie chart in terms of clicking what you need, the number of pixel in a straight line are the ones that count, I believe that the fundamental difference in Raptor navigational system helps a lot giving a much bigger hit space that conventional menu systems.
screenies that exemplify.
I tried 2 common mouse movements in each solution (note that the span of the mouse movement in raptor should tend to be smaller cause of the placement of icons according to mouse zero point and usage database)
"T is the average time taken to complete the movement. (Traditionally, researchers have used the symbol MT for this, to mean movement time.)
a represents the start/stop time of the device and b stands for the inherent speed of the device. These constants can be determined experimentally by fitting a straight line to measured data.
D is the distance from the starting point to the center of the target. (Traditionally, researchers have used the symbol A for this, to mean the amplitude of the movement.)
W is the width of the target measured along the axis of motion. W can also be thought of as the allowed error tolerance in the final position, since the final point of the motion must fall within ± W/2 of the target's centre." (in wikipedia)
So the only 2 things we can play with is D/W ratio, since all other aspects do not depend on the actual positioning of the objects, and the smaller it is the better we are, so results: case 1 =3,44 case 2 (raptor) = 1,91. meaning Raptor clicking is almost 50% faster.