Wikipedia has a principle called assume good faith. That is, if you see an edit that seems unhelpful, your default assumption should be that the author intended it well - until they demonstrate otherwise.
Do we need that here?
You might think, "well the good posters don't need it and then bad ones won't pay attention". But I think many posts fall into a gray area: they're not abusive but are pretty harsh. Consider, for example, the "why don't you check out Google before posting?" remarks. Instead, why don't we default assume that the poster has done their research - unless they go on to show that they clearly haven't?
This would help prevent defensive posts - people justifying their posts - or worse, people not posting at all, for fear of the harshness that I see too often here.