Re: Should everyone teach?
IMHE there is a very big difference between being sempai and being a teacher. As sempai I have the task to help anyone junior to me in a lot of aspects of the training hence relieving my teacher of this burden and thus ensuring he can focus on teaching his thing. Simple things as reigi or helping people with their obi etc should not be my teachers burden. Even within the lessons I have the task of being an example, to train with beginners to give them a feel of what is going on etc and to correct any behavior which could result in immediate danger.
I do not teach, period.