Re: what would you do?
If I ever heard one of my shodans say to people/students that "I am just a shodan and am here only to help with the basics simple stuff", he'd be a white belt again so fast he wouldn't know what hit him. When you put the black belt on, you did something to earn it. If your instructor(s) have enough confidence in you to promote you to shodan, you'd better be able to show that confidence when you are teaching. If you don't know the answer to a question, it's perfectly acceptable to tell them you don't know BUT will find out the answer and get back to you. That's a leader and shows confidence. You'll get a lot more respect like that rather telling them that "I am just a shodan.............."
You don't have to prove yourself to anyone on the mat. If they ask me if aikido works, I usually tell them it depends on your attitude and how hard you practice. What you put into it is what you get out of it. Just because it doesn't work for you doesn't mean it won't work for someone else. If you radiate confidence, believe me the students will read it.
"I am just a shodan..............." is the ultimate disrespect to your instructor(s). Why would your instructor(s) promote you if you didn't know anything???? All I can say now is God help the student of mine that says that and I hear it.