Excellent point. My son isn't at the age for school just yet, but we'll be reminding him of the hierarchy constantly, as well as the reasoning behind it, just as you have done. I've worked with teachers before (and am one now). Teaching is a skill like any other, but it's definitely a very mixed bag. I'd not hesitate to say that most teachers are losers who couldn't make it anywhere else: those that can't do, teach.