Not long ago, in a classroom not far from where I live, I was sitting in a class (how ironic, being in a classroom). In this class the teacher was teaching stuff I’ve heard before. I wasn’t ornery or upset or anything, but I was tired. Wishing I was still in bed, I didn’t think it was worth my time to review the material again. Then, I realized I had an awesome opportunity. I got to review the material again! I recognized that I didn’t know even a small percentage of what was to be learned from the subject. This change in attitude came quickly and when it did I immediately started learning. I walked away from the class happy that I’d woken up to go. It put me in a great mood for the rest of the day.
Don't discount re-experiencing something you already know. There are people out there who are providing a point of view that you may never have heard before. That unique viewpoint may be just what you need at this particular point in time. - Tony D. Clark, The Point Of View May Be New To You
In my example I was learning from the same person both times the material was taught. This doesn’t, however, mean that the experience could be discounted. I dare say that even if you listen to someone teach the same thing several times word-for-word, if you open your mind to learning, you will learn.
People need to be reminded more often than they need to be instructed. - C.S. Lewis quoting a "Dr. Johnson" in Mere Christianity, Social Morality
All of this does not mean, of course, that if you are the one teaching that you can be lazy and recite the same exact thing every day for the rest of your life and expect people to listen to you. heh.