My friend works for Criterion film company and he just finished editing this movie. I thought you might find this clip of it funny.
From the site:
As you can see in this short special feature from Criterion’s release of The Great Dictator (out next week on Blu-ray and DVD), which compares Charles Chaplin’s 1940 masterpiece with his brother Syd Chaplin’s 1921 silent comedy King, Queen, Joker, both Chaplin siblings were captivated by shaving scenes set in barbershops. Watch how their techniques converge; it’s all in the wrist.
There doesn’t seem to be a way of embedding the video here so CLICK HERE to see the video.