Bertolt Brecht used the German term Verfremdungseffekt (don't ask me to pronounce it) to define the authorial choice to force a distance between the audience and the character. This is of course antithetical to the more common desire to encourage the audience to identify with the character. This choice to estrange the audience from the character is often accomplished by making her unappealing or her actions incomprehensible. The point is, I think, to force us out of the comfortable companionship of thinking, "She is like me, and therefore good" and into evaluating her more objectively (and perhaps evaluating ourselves more objectively).
Brecht's most famous expression of the "distancing or alienation effect" is in the title character of his play Mother Courage. He wrote this while in self-exile from his native
during Hitler's reign, and that might give us some idea of why
"distancing" or "alienation" might have been a particularly
valued goal at that point in history. Germany
What's interesting about this choice is that it discards the enlistment of an audience's most valued ability, empathy, in order to present human action and interaction in a more unsparing fashion. Brecht meant Mother Courage to be a more "true" representation of humanity perhaps than a character shaped to draw the audience's fellow feeling. Techniques that can cause the alienation—well, the most important would be presenting the character's action without justification, and the character's flaws without mitigation.
That was what Brecht was playing with in Mother Courage, alienating the audience from her by using her as a representative of the capitalist and mercenary set. I think he wimped out enough -- making her a mother who loved her children-- that the audience wasn't nearly as appalled by her as he wanted, or maybe we just naturally have fellow feelings with most other humans. In fact, I tend to think that characters who are presented rather starkly in their unappeal end up winning the audience over (Sherlock Holmes, Scarlett O'Hara). I might go so far as to say that characters who are hard to identify with early in the story are often the ones who attain sort of cult status or become cultural icons like Sherlock.
Without the easy empathetic identification, the audience will have to judge the character on her own actions and interactions rather than empathy. I think when it works, the audience ends up really in deeper identification because they have to really think about how and why this character is this way and does these things. It's like you might love a difficult friend more because you actually had to work to love her at all.
I'm wondering if comedy might rely more on distancing—we don't, after all, laugh at ourselves usually, so too close an identification with the comic character might diminish are ability to find those pratfalls funny.