Ake:

Those who know their posts can be ambiguous and can hurt if taken awry use smileys to clarify their intent because they care not to hurt unnecessarily. Not everyone does, of course, but you asked about those who go to the trouble. Not because our satire is insufficient, or our confidence in it low, but to avoid paining innocent bystanders. We also appreciate that not everyone is subtle enough to avoid pain on their own. :>)

A