Good question! Well, the offset function is a huge time saver, and by all means, it's here to be used, BUT we animators should be well aware when and how we use it. Idle is the best example of how easy is to offset the body parts around and get naturalistic movement. But for walks, runs, attacks, etc. I never offset body parts, I always build the movement into the pose. This way I never get disjointed movement and my poses always feel solid. I would recommend this practice to everybody, to always think of your golden poses and how the body functions in relationship with each other.
Veteran Disney animator Eric Goldberg best known for animating the Genie in Aladdin often talks about what 3d animation misses from 2d, and its exactly this issue, how very often you don't feel this clean golden poses as everything merges together, body parts tend to "swim" around (btw. he has an awesome book that I would recommend - Character Animation Crash Course!)
In resume, the offset function, definitely awesome. But take mental notes when you are using it, so next time you can build this into your pose and your posing gets better. I actually tend to use offset on tails, cloth, flags, stuff like that. But, I know my poses, so offsetting is just a time saver and I approach my animation with this thinking in advance. Everything that is body mechanic, first I try to understand the physics to pose it properly, so I store the movement into my visual library and I can easily animate it next time.
Hope this helps, let me know. And feel free to ask if you have some case-specific thing in mind!