Past efforts to do that kind of thing haven't worked, so I'm a bit down on the idea. What ends up happening is (1) the meta communication stirs up a flurry of objections, some relevant and many not; as well as people passionately restating what they feel about current affairs and/or how much they dislike what some other comment said; and at the same time (2) most people still don't see it, so it ends up not having the desired effect and just taking a ton of time.
Somehow, no matter how often we repeat something, the set of users who hear it always has measure zero (https://news.ycombinator.com/item?id=25787443). That's why I mostly stick to answering specific comments with detailed explanations, and hope that at least some other users will see it.
There's something a little interesting in the measure zero observation; we've run into it in a couple places too. For instance: we now do voice calls ahead of our last hiring exercise (it's a little bit counterintuitive and needs some prep) because no matter how carefully we wrote about it, even with highly motivated candidates (many of whom we statistically end up hiring!) nothing we write seems to sink in. We have an API quirk that works the same way, too.
Somehow, no matter how often we repeat something, the set of users who hear it always has measure zero (https://news.ycombinator.com/item?id=25787443). That's why I mostly stick to answering specific comments with detailed explanations, and hope that at least some other users will see it.