I ran a message board once.
One thing I learned is that you cannot tell users to do anything and expect them to do it. It's like a road. If you want people to drive fast, make your road wide and straight. If you want them to drive slow, make it narrow and twisty.
But if you build a wide straight road and post a 25mph speed limit on it, people are going to tend to ignore it.
Or, to use a different analogy:
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