I think there's a world of difference between "the company is out to screw me" and "I want the best possible result". And I think that the throwaway account you're agreeing with has trouble differentiating between the two (see my other responses to him).

It is absolutely reasonable to enter a negiotiation with the intent to base the resulting partnership on mutual trust. But "I will renege on this offer if you attempt to negotiate" doesn't scream trustworthy to me.