It just so happens that Steve has posted a follow-up to his previous letter in Japanese. This time he recorded his thoughts in Japanese. I listened to it and I understood 95~99% of it. He talks about the advantages that adults have over children in language learning. And it's true, of course. Adults have much more life experience and knowledge than children have. That's important for learning anything. The more you can relate to what you are studying, the easier you can learn it.
One of the worst is when someone tells you that what you are studying or what you just said is not used at all in the real world. They will say something like, "That is textbook language. We don't talk like that." Or they might say, "We never say that." And note, I'm saying that even native speakers will do this! For instance, I remember one teaching all her students that we never use the word "hobbies." I was teaching at that time. That wouldn't have bothered me so much but it seemed to be her theme for the day. Every period I heard her saying, "We don't say, 'What are your hobbies?'"
Well, what is the harm in students using perfectly good language? It doesn't matter if there is another way to say it. If it has been learned already then there is no need to use any negative language. Discouragement is not necessary and could have a negative effect.