Wow !!! You really hit those out those two Q's out of the park. Can I ask two more Q's? 1. Why do you think it's good to stretch your comfort zone when it comes to physical activity (e.g., first-timers braving fitness challenges, whether CrossFit or Bikram yoga)? I think the idea is to seek out challenges and then get comfortable being uncomfortable to build mental and physical muscles. Pushing oneself to one's own edge, that's how we improve. The goal is to get better, the change comes from effort. Also take a cue from elite athletes because they are very practical. They are going to put in their all, but they also listen to their bodies. 
2. How can folks overcome intimidation when trying something new at the gym? I think they need to manage a) physical discomfort -- stop worrying how much its going to hurt (i.e, develop high-frustration tolerance), and b) master social discomfort -- stop comparing self to others others (i.e., set your own standard and raise the bar accordingly). What do you think? Thanks Jack! Jim