If your given the task to teach... teach.
This past Tuesday a 2nd kyu was told by the instructor to lead the class as the 1st kyu was late.
I was wondering if it would switch once the 1st kyu showed up, but didnt.
During training the 1st kyu did pointers with who he trained with, but no big deal, I gave pointers even to 3rd kyus when I was 6th kyu. [basically I saw something the teacher did and relayed it back - though that can still throw someone off if there is the ego at play]
I guess the point is you do what you can do, and if the arrangement is for you to teach, and he is fine with that... no real problem.
The only problem exist due to the line of authority we believe to exist. We grew up with linear thinking. A baby can teach us about life just the same as a wise-man. [a lesson is to be learned everywhere.]
Sure sounds nice, but its easy to blow off as we truly are conditioned to this linear way of thinking.
If hes better than you, no shame in taking some advice when he trains with you, and people should not be discouraged to see this take place either - but it should encourage them to see what they have learned and gotten out of it where they can share part of their aspect of learning with others when they train as well.
I understand the feeling your talking about, but its all good.