I am not sure how one arrives at the conclusion that constructive criticism is not allowed here. It does seem clear that there are two ways of expressing constructive criticism: harshly and kindly. In my experience, kind constructive criticism is actually more constructive and therefore more skillful. The only time I speak harshly is when someone is about to cause immediate harm to themselves or others. I have told people that they will die in less than 5 minutes if they continue with what they are about. But even then I would not say, “stop that stupid behavior now!”. It is kinder to say, “Please stop, you will die if you continue doing that and I need you to drive me home.” They stopped. And yes. They would have fallen to their death and died.
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