Hmm, I wouldn't call this fear, more like paranoia, but when I have to write something (especially philosophy stuff GRRRR) from a purely logical perspective, I always think my arguments or critiques of other people's are never that strong. I suppose I do have a sort of visceral fear of confrontation in general, but four years of working customer service at a bank kinda forced me to face up to it. Still despise it and avoid it whenever possible though. In this regard, I think your super-ego hypothesis might have something to it.