Additionally, in The Book Of Water, Miyamoto Musashi notes that stance is an important part of "strategy" (suggesting eye contact is not seperate from facial expression or body english) He wrote: "Adopt a stance with the head erect neither hanging down, nor looking up, nor twisted."
This is part of what Musashi notes as *wedging in*. "Weding in" - eyes straight ahead is an interesting idea for creating a space through a group of people one wishes to move through, etc. Maintaining a *distraction free* headspace no matter what was going on in the immediate surroundings, was an all important part or Musashi's methods.
In regards to the *Gaze* of someone, Musashi notes that a person must be able to perceive that which is all around them, *without* moving their eyeballs noticeably which is said to be a skill which takes an enormous amount of practice to perfect. Have tried this while driving - basically actively using peripheral vision without moving the eye - way fun and way hard. :-)