Yeah, if you join a Crossfit-specific gym, take the advice of the people there with a grain of salt. They tend to practice with an any means necessary approach to completing the weight or task, often throwing form out the window and putting themselves at serious risk of injury. Specifically, I seem to remember seeing newbs under too much weight trying to do things like squats, deadlifts, clean and presses, etc. where bad form means fucking up you spine (Squats and DL), or snapping your wrists (Cleans). Youtube "Crossfit Injury" and then try to understand the proper form and technique for an exercise that you are unsure about.