I mentioned "selective forgetting". If the ego can't reconcile actions or events with self-image, it can tell the department of records to erase the evidence before any broadcasts are made. Such material can make its way into consciousness - but after examination it gets rejected and there then follows a cover-up operation - which can sometimes look a bit like: http://en.wikipedia.org/wiki/Repressed_memory

One advantage of this is that more sophisticated methods can be used to determine what gets rejected. One disadvantage is that the forgetting process can be imperfect.