Rationalist: Information is best transmitted by a reasoned approach: defining the question, hypothesizing an answer and presenting an argument to support this. Logic. Logos.
Narrativist: People pick up information through stories, too. Set a scene, set a problem and show a solution. Emotional involvement. Pathos.
Perhaps there is not such a great difference here. Both paradigms are three step processes. Both progress logically and sequentially. Both have a beginning, middle and end.