We can use Fitt’s Law?

It’s not everyday I recognize something from the Human Factors courses I slept through: mezzoblue § Fitts’ Law. Now, if only we can make use of Therbligs to analyze motions during user interaction…

A larger clickable area means less precise mouse movement is required to focus on the link. Without impacting the design in any way (the halo is non-visible after all) the usability of the header improves.