Last weekend, two climbers were enjoying the classic five-pitch Nutcracker (5.8) in Yosemite Valley. On the third pitch, the leader placed a cam roughly 10 feet out and started liebacking his way up the granite splitter ... until he slipped. When the rope came taut on his single piece of pro, however, the cam blew out of the crack, sending him for a 40-foot plunge onto the anchor.