> Looking forward to the NALs responding why this is terrible.

My NAL guess is that it will go a little like this:

* Candidate makes disparaging post on reddit/HN. * Gets many responses rallying behind him. * Company (if they notice at all) sues him for breach of Non-Disparagement-Agreement. * Candidate makes followup post/edit/comment about being sued for their post. * Gets even more responses rallying behind him.

Result: Company gets $10.000 and even more damage to their image.

(Of course it might discourage some people from making that post to begin with, which would have been the goal. You might never try to enforce the NDA to prevent the above situation. Then it's just a question of: Is the effort to draft the NDA worth the reduction in risk of negative exposure, when you can simply avoid all of it by not providing feedback.)