Obviously they gloss over some of the details, like the exact energy transfer numbers - but it does give a good overview of some of the Snell standard test procedures
http://hellforleathermagazine.com/2010/02/a-look-inside-bell-helmets.html (http://hellforleathermagazine.com/2010/02/a-look-inside-bell-helmets.html)
The comments had me laughing so much, I forgot to watch the video! [laugh]