The seminar is called “Unleash the Power Within.” The multi-day event with world-renowned motivational speaker Tony Robbins is “designed to help you unlock and unleash the forces inside that can help you break through any limit and create the quality of life you desire,” according to promotional materials. “Overcome the unconscious fears that are holding you back,” Robbins’s site proclaims. “Storm across a bed of hot coals. “Once you start doing what you thought was impossible, you’ll conquer the other fires of your life with ease.” But Thursday night’s coal walk in Dallas didn’t go so well for dozens of...