"The fact there isn't a private dislike button (that no one sees you clicked other than Facebook), is remarkable at this point. It's either woefully obtuse, or intentional so that a feed of false positives better hides moderately targeted ads."

I vote the last option. I think there was an explanation, basically saying it would make people upset or sad and they wanted to avoid that. The solution wound up being a variety of emotions to pick from (which counts more than a simple like). They included negatives like "angry" or "sad".... I'd still just rather have a simple dislike button.