Why is it that Bill Cosby’s routines never get old? I watch “Brain Damage” today and laugh harder than I did twenty years ago. (Maybe because I’m a parent now.) Here, blogger Garr Reynolds has compiled a few of Cosby’s classics, along with his recent commencement address to CMU grads, with the purpose of pointing out how enduring the power of personal narrative can be. Reynolds’ bottom line: funny or not everyone has personal stories worth telling.