I haven't seen any constructive criticism there.
Added 1 minute ago
why? I didn't offer to teach anyone. You decided to teach someone, and if that's the case, then you should be able to do it and have some knowledge. If you can't, why did you interfere?
Added 4 minutes ago
In general, the position of "I don't know how to do it right and I won't, but you're doing it wrong, so don't do it" is annoying. Passivity. Stupid, useless passivity. If people listened to it, we would still be living in the Stone Age. Or we would have gone extinct altogether.

