One thing that it seems people often forget is that, in business, if you're truly entering in to mutually beneficial agreements (whether it's hiring someone or being acquired), both sides generally will try to come to some sort of arrangement that makes sense for both sides. In other words, when it's understood that an agreement is win-win, then both sides are motivated not just for themselves but for the other side as well.
Of course, the sentiment is a bit idealist, as the hard part is actually figuring out when someone is being genuine and knowing exactly what value you're providing to them and they will provide to you. If a company really wants to buy you, and they're not trying to pull one over on you (e.g. intentionally offering much less than your value), then they won't try to strong-arm you into doing something you don't want to do. I think this is what the author is getting at when they say that it's okay for you to push back on things such as offer price, deadlines, etc. The key is to also be genuine and not try to pull one over on them.
Of course, this sentiment is also a bit idealist, as the hard part is knowing what your actual value is to the other party, as there's seldom an absolute value of something; it usually depends on the situation of the environment and other party, which constantly changes and which you won't have the full story.
This also assumes that genuine parties are wholly genuine and that they're not being led astray by other parties, whom they absolutely trust but who may not be genuine or as capable as they have led the primary parties to believe. I've seen plenty of deals fall through, or almost fall through, because of good people being influenced by outside factors.
I kind of lost my point in all that. I think it was simply that, while acquisition talks are stressful and time consuming, they can also be scary. That fear however, usually comes from doing a deal in which you may feel you're misrepresenting your value (and thus trying to get more from the other party than the actual value you're providing), or in trying to do a deal or negotiation which you feel you absolutely cannot walk away from. Both of these situations lead to more volatile negotiations which fall apart more easily. And this can lead to making the wrong concessions or agreements, which gets us back to one of the points in the article, which is that the best time to solicit an acquisition is when you don't need it and can easily walk away.