The reply that wins attention may be less useful than the reply that answers the question.

Sharpness travels further than helpfulness. The clever response gets read and repeated while the plain, correct answer sits underneath with almost no attention, and it becomes very easy to start writing for the room instead of for the person who actually asked something.

Before you post a reply, ask whether the person would be better off for having read it. If the honest answer is no, and it is really there to be admired, leave it unsent and answer the question instead.