Hostage negotiation is a game played once between parties. Most of daily life situations are repeated games, in which dynamics are different. I found that the author was biased by their experience in one-off games and their suggestions wouldn’t generalize well into repeated games. Unfortunately, there is no acknowledgement of this until the very end of the book. Still a good read though.
Yep I agree on one hand but on the other, getting to that point is being 95% out the door anyway. Even if you stay, many managers and businessmen have very persistent bad memory and will remember you as the guy who twisted their hands or whatever. I've experienced this a long time ago; some of these people are very resentful and vengeful.
Often times staying at a place where you have thrown the "I'll leave for a better offer if you don't budge" card on the table successfully... is not worth it.