12 years ago: "this is interesting and maybe quite comfortable to use"

Now: "please view the entirety of this video ad to continue"

The data on comfort using eye tracking is fascinating (4.5 Results and Discussion):

  Participants complained that staring at so many targets made their eyes dry and uncomfortable. Eye fatigue scored lowest among all the questions. Participants gave eye tracking a modest favorable response overall of 4.5, just slightly higher than the mid-point.

A bit tangential but my limited experience playing star citizen with eye tracking technology was exhilating.

With the technology out at the time (and the little i could do with it) i was mostly limited to exaggerated eye movements.

Repeated "full side eye" gestures were definitely uncomfortable (physically) and at times somewhat nausesting.

After a few weeks of steady gameplay things were noticeably better but still not something i could maintain without discomfort for more than 1.5-2hrs.