Does holding a cell phone to one's mouth create some sort of perceived private space, and once that is removed we feel uncomfortable or agitated to hear someone's conversation? If we can't see the headset, does that make us even more annoyed, and why?
I think you nailed the reason I dislike D-bags on their headsets...
A great example,
I'm walking down a city street- a man approaches from opposite direction walking toward eachother, eyes meet as any normal human eyes should, and four feet in front of me, he says "Hello" - I respond as if I don't recognize him, because I don't, and he looks at me, nearly upset or aggrivated, and points at his ear with a rude thrust, like I'm the a$$hole here. That instance, made me hate that guy, and most other users.
It's happened to me several times, standing in line, someone directly behind me says "Hey" at normal speaking volume, I turn around, and they're annoyed at my response of even looking at their face
I think the 'arm up' certainly creates the personal space,
it's a natural human reaction for defense, bring your arms in, create your own space, a shell sort of
or if the arm is out at a 15-20 degree angle bent at the elbow, that adds a bit of distance to the horizontal area you're taking up
it's a clear and communicated way to tell the world "I'm on the phone"
the simple fact that people will "fake a phone call" to avoid an unpleasant situation or discussion by putting the unit up to their face or ear. this should be a major flag in this research. by using this physical motion, others will see it, understand it, and 9 times out of 10 leave the person alone. strange, but true.
where the headset users are walking around, talking, staring ahead, it makes think they're insane, or maybe that I've lost my mind
A step in the right direction is by adding one of those bright lights on the exterior to show "I'm on the phone"... but that still doesn't work too well in my opinion
There has got to be a better explanation why I too, dislike those things so much