Isn't there maybe a class insignificant harms where net utility is neutral or even positive (learn to squint or where goggles in a duststorm, learn that motes in ones eye are annoying but nothing really to worry about, increased unerstanding of Christian parables, eg; also consider schools of parenting that allow children to experiment with various behaviors that the parents would prefer they avoid, since directly experiencing the adverse event in a more controlled situation will prevent worse outcomes down the road). I'm not sure you can trust most people's expressed preference on this.

That being said, I don't know where that class begins and ends.