It's like an asymmetric game of chicken. Both players know that the troll has the advantage of having less to lose in a "collision" (a lawsuit), so the troll can count on the victim to "swerve" (settle). If the victim was able to eliminate the cost of a collision, and the troll knew that the cost of a collision to the victim company was eliminated, it would make more sense for the troll to swerve (drop the claim).
(More chicken strategies here: http://mindyourdecisions.com/blog/2009/01/20/4-tips-for-winn... . This strategy is most similar to #3.)