/Agree with above posts.
I have seen the majority of personal trainers not keep track of their clients progress or exercises.
I understand the thought Mercedes Dunn has of concentrating on the other aspects, but as the professional in the gym, I always assume the person I am working with has ZERO prior knowledge of how to workout. I explain everything I do and the reasoning behind it.
Knowing where my clients are at is of paramount importance, and it gets more so when I get especially busy. Its hard keeping track of 3 or 4, let alone 12+ clients.