Too often stress and reduced effectiveness are blamed on surprises. If you know what you're doing and what you're NOT doing, surprises are just another opportunity to be flexible and creative, and to excel.
You can have all the other levels of your life and work shipshape and defined to a T. Still, if you're the slightest bit off course in terms of what at the deepest level you want or are called to be doing, you're going to be uncomfortable.