It is always a good idea for longer endurance events to have a goal range. It can be a tight range but a range non the less. The primary reason is that you never know what kind of conditions may confront you on race day. A strong head wind or a very hilly course for example can cause you to run slower than you may like. The most important thing to consider in longer endurance events is the effort you can sustain for the duration of the event, not necessarily the pace.
Posted in: Goal Times and Effort