Maybe it would be better explained if I said it this way...
Teach your students so that what took you years to learn, they learn "quicker" or without all the "searching" you might have to do to learn particular techniques. The longer you have a technique in your arsenal, the better you can use it comfortably.

To answer your second point, I've always taught my students so that they would excel, even beyond what they "know" currently. My senior student told me this weekend that things I taught him 10 years ago were part of his technique, but he was just now being able to explain them...
I think that's making him better... it was certainly my goal while training him... but he still comes back to the well for a drink once in a while... He's learned a lot on his own, and when he does, he applies what I taught him to it, and he himself has told me it's made him much better. He's now 44 and I'm 62, so I might be a bit behind him physically, but he's gaining on me in martial arts mentality and understanding. He knows that I still have things to teach him, so he'll never admit to being on my level or "equal" to me, but I wouldn't be proud of him if he wasn't the way he is. I'm still "junior" to my teacher, even though I outrank him and am in better shape. He likes me because that I took what he taught me and expanded it... just like he taught me to do...

I think our attitudes make all of us "worth our salt" if we're teaching, training, and extending ourselves in the effort to improve martial arts understanding. My teacher said "pass it on"... so that's what I do...

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What man is a man that does not make the world a better place?... from "Kingdom of Heaven"