It has to do with self knowledge. That you constantly have to be aware of your feelings and thougts. When you can distinguish a feeling from another just like a tree from a bench you can say something like "delete" or whatever you want to say to get rid of it. Think its sort of the same when meditating. Your trying to not getting involved in yourself, but objectively looking at yourself. And then you can catch yourselfs(egos) in theyr act. I took this course on Mystical Web. At the time i thought it was both great and fun. But now its just to old fashioned and mystical for me. But if you look between the lines so to say and convert what you read to the year 2004 there is pretty much good reading there on differnt estoric topics. If you want i can send you the whole course somehow.

But i also have a pretty good link here to, that speaks about egos: http://www.deoxy.org/egofalse.htm
Deffintly worth reading.