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[K00l Secrets]

> Shaving probably will not be a problem, but holding your head at a
> slightly different angle...  will screw up the system totally,
> unless the system has radically improved since the last time I read
> up on it.

Well, the systems I have seen are quite good at finding people's eyes.
Scaling (for distance), and rotation (for the angle of your head)
therefore don't really confuse the system once it has your eyes.