The title of this small post is a bit provocative. I have no doubt the idea of Critical Path is a key concept to understand for any program manager. Critical path is a useful heuristic. But heuristics can be abused, or overused at least, and I have come to think that we lean far too heavily on this one.

Why? My schedules are my best single-point estimate at a instant in time, but they are inevitably wrong - especially at the early stages of a program. If your plan’s estimate is correct, or nearly so, then watching your critical path is enough to ensure you deliver on time. But, all plans are wrong. If you believe this tenant to be true, then you don’t really know your critical path. What you need to do, is be prepared as possible when a surprise causes a change to your plan and critical path. Having multiple options to complete your program is one of the ways to make your program robust to surprises, and nothing gives you options like time to react. Leaving everything for the last minute robs a program of an opportunity to recover from the surprises that occur later on.