I am a full supporter of SS!
The best way to learn is to teach!
Did Jesus forbid us to separate people?
Did Jesus command us not to separate children?
"When I was a child, I spake as a child, I understood as a child, I thought as a child: but when I became a man, I put away childish things" I Cor 13:11
Timely post from my standpoint. I've been asked to sub this Sunday for our teacher who has to be away this weekend. There shouldn't be any need to explain the difference between sitting in a class and standing before one, in terms of study required.
Another point that you didn't mention is the responsibility that each of us carries to help brothers and sisters grow in maturity in the word, the Word. Putting that responsibility solely upon the pastor's shoulders is shirking our own responsbilities, IMO. No, not everyone can teach, just as everyone can't stand in a pulpit and preach a semon. God doesn't call them to do so.
However, when God puts us in a teaching position, we are supposed to do it, just as Moses did, despite protests about his limitations.
I'm not a teacher. I'm a basket case of nerves when I have to stand before people and speak. The words, that usually flow easily from a keyboard, often stumble and falter when I speak. Compound that with the realization that some in this class probably have forgotten far more than I'll ever know about the Bible.
Also realize that God has a purpose for putting me in this position Sunday. The why I may never know. It may simply be giving an opportunity to assume the responsibility, in us all, to help brothers and sisters grow. Not only for the help that I can give. Perhaps, it's actually an opportunity for others in the class to help me when I falter.