alanbailward

See my other answer, but the short version is it does make facial recognition software work better. I'm not sure if it's variations on the facial structure, or what, but my boss worked on the facial recognition software in the '01-'02 era, and it worked with more accuracy with no smiling.

I can't answer this on the site, but my boss claims that he was partially responsible for this. He worked with the company doing facial recognition software to hunting down kiddie porn makers, which was (I think) moved into terrorism detection (this is in the 2001-2002 timeframe). They couldn't get the facial recognition to work with enough accuracy with anything but a blank facial expression.