I'm another old fart, and always wear ATGATT. Was recently reminded just how fragile is my skin when on a hot summer day in Virginia I stepped from a low light interior into a bright sun and missed the 1st and only step - about 3 inches - and hit the asphalt parking lot. Wearing only a T shirt, my right forearm, took most of the fall, receiving abrasion from wrist to elbow. Only took 2 days for the pain to subside, and 2 weeks to completely heal. Multiply that small area and those durations by who knows what number to find the time to recover from a fall at 20, or 30, or 60 mph. I'm a believer.