This article was originally supposed to have been based on a poll I conducted this week on schedule compression techniques. However, a discussion from a project management fundamentals course I taught was too compelling to not share!
While teaching the basics of the critical path method, I asked the learners whether it was possible to have more than one critical path in a project’s activity network diagram. As the class understood that the critical path represents the longest sequence of activities from start to finish, they all agreed that this was feasible if you had two or more paths with the same total duration.
However, one of the learners indicated that one of their clients refuses to accept project schedules from contractors which show more than one critical path. When the learner told me who the client was, I was surprised as it is a well established, large organization.
I asked how he deals with the situation and he indicated that when the software they use calculates more than one critical path, they modify the scheduling logic within one or more of the paths to ensure that there is only a single critical path.
It is possible that the client is concerned that when a schedule has more than one critical path, there are likely fewer activities possessing float or slack and hence the potential for a delay to key milestones or the overall project end date is greater.
However, this is also true when you have network paths which are close to the same total duration as the critical path. I’ve seen cases where project teams and senior stakeholders focused so much on the original critical activities that they ignored the fact that sufficient delays had occurred to near-critical activities such that a new critical path emerged.
Regardless of the reason why the client had this requirement, such concerns shouldn’t result in artificial changes to a properly-built network diagram.
Not liking the facts doesn’t make them fake.
(If you liked this article, why not read my book Easy in Theory, Difficult in Practice which contains 100 other lessons on project leadership? It’s available on Amazon.com and on Amazon.ca as well as a number of other online book stores)