It's a very interesting shot, right?
Mr. Smith, yesterday while I was surfing cinematography.com I saw that Mr. Hart was a member and I emailed him too, the only thing I forgot to send him was the picture.
About the mimicking, seems very difficult, because the movements match perfectly.
If you don't have the movie, you can watch the clip on youtube: http://www.youtube.com/watch?v=rkhFfv-tkGE
Let's see if we get an answer for this mystery!
Thanks to you all!