It's a really good read about when to fight, and when to walk away (cue The Gambler).
The whole thing is worth a read, but this line really struck me:
This also applies to internal company decisions. Let’s say a senior member of your team demanded a pay increase (cash or equity) and you didn’t like the way he or she approached you. Sometimes the right thing is to firmly but politely resist the increase. Sometimes the right thing to do is to give in completely. And sometimes the right thing to do is to compromise. If you do decide to compromise then don’t be snide or mean-spirited about it after the fact. If you’re going to give him a victory then lavish praise on him as you meet his request. There’s nothing worse than consenting to the increase and having him feel pissed off about it. You lose twice.(bold, italics mine).
Losing sucks, and I've watched some really unethical behavior go unpunished, and that sucks too. However, at the end, it's the final prize that matters. Mark's right, take the optimal path, and if that involves "losing", then don't lost twice.