At 1:29 of the video, “Gazespeaker eye tracking and Google maps” (http://youtu.be/BwZ3YCo73RE?t=1m29s), a user has the intention of activating the “See Map” icon, but the user has to keep on restarting their dwell, as the point of gaze keeps on leaving the hit state of the target.
It takes five dwell attempts in order to activate “See Map”.

GazeTalk – free, predictive text entry system

GazeTalk is a free, predictive text entry system by Gaze Group: http://wiki.cogain.org/index.php/Gazetalk_About.

Notable feature of GazeTalk: accumulate dwell time: resume dwell time after looking away

If any jumpiness from eye tracking, or if a brief, voluntary withdrawal causes the fixation on an intended button to be interrupted, GazeTalk has the option to recognize a resumption of the dwelling, and continue building the dwell time for that particular button.
GazeTalk has an “Accumulate dwell time” function to “avoid the re-setting of a button”.
That is, you don’t have to start over again.
A successful activation of one button resets partial dwell time buildups in any other buttons.

Indeed we will include this feature to avoid losing the dwell selection inadvertently or because there was some involuntary eye movement detected in the eye tracking position.

It seems easy to implement (already did the change in the dwell algorithm and it works fine). We will do additional tests and release a new version with this feature in the next release planned next week.

Pierre