Well now I feel like I'm having a conversation with John instead of the forum, but oh well!
This style of communicating requires a lot of trying to construct what a person is like, but the problem is the complete lack of objectivity involved. Our own wishes, biases, beliefs, etc all conspire to mentally invent a person- and of course you can be very wrong! Needless to say, 'first impressions' in 'real' life can end up being awfully wrong as well. I'm sure, John, that the nature of this internal processing (which can be a very active one-- which I find to be fun by the way) is dependent on lots of variables. The degree to which one is conscious of their influence on other people is one issue. How carefully people read posts may have some relationship to how carefully they listen in face to face communication. I think the most interesting part of cyber communications is trying to detect 'affects' accurately. Normally the human face is an extraordinary communicator of feeling (actions and reactions). I suspect that when the face is eliminated from the conversational process, an undercurrent of distrust never quite disappears for many people.