I started experimenting with eye-contact several months ago and my results were very similar to what it being reported. At first, the act was unnatural and it required mental exertion in order to not reflexively look away. After a while it became more natural and almost a game. The responses from the women in particular were the most interesting. The most feminine women seem to hold eye contact the longest, although I work with a lot of engineers, YMMV.
The anonymous comment is funny but insightful:
Roissy needs to put a warning label on this post. Eye contact is a sign of aggression.
Obviously not all eye contact is a sign of aggression and there is more to your overall body language that plays into this, but there is a very large kernel of truth to holding eye contact being an aggressive act. This would explain why most people are uncomfortable initially because at some gut level they feel it would be committing an act of aggression which they are subconsciousness trying to avoid. Perhaps aggression is the wrong word as that is not the right frame, I think it is more of a lack of fear which at times can be apprehended as aggression.
Speaking of fear, I seem to remember some game commandment that has to do with fear. Ah yes, of course. Le Chateau. Fearful breaking of eye contact does not convey confidence.
XVI. Never be afraid to lose her
You must not fear. Fear is the love-killer. Fear is the ego-triumph that brings abject loneliness. You will face your fear. You will permit it to pass over and through you. And when your ego-fear is gone you will turn and face your lover, and only your heart will remain. You will walk away from her when she has violated your integrity, and you will let her walk when her heart is closed to you. She who can destroy you, controls you. Don’t give her that power over yourself. Love yourself before you love her.