Keith, a great post. Let's hope the video surfaces sometime soon. If I recall correctly Chris Vicary in recent years had made some attempts to contact Dr. Gregg's family for some follow-up.
We are also fortunate to have Phil Waterman, who attended ' CMP Seminar '84 ' as a major contributor on this Forum and someone who so readily shares his CMP knowledge on his own website.
http://canadianmilitarypattern.com/
Brian