I finished reading for the second time “Critical Chain” by Eli Goldratt. I find the Theory of Contraints (TOC) to be intellectually satisfying: the idea is simple (although execution is not); it makes common sense; and it resolves some of the more persistent and difficult problems in project management. But I have never implemented TOC in my projects. I use the traditional methods for measuring performance: budget to actual, milestone completion, and % complete as compared to expected completion. These are useful metrics, and perhaps the greatest value in them is that most people understand them.

The downside of these metrics is they obfuscate expected performance. This happens when non-critical tasks are completed ahead of schedule. Completing non-critical tasks push the % complete up, or make Earned Value look better, even though it does not improve overall project performance (by that I mean meeting expected timelines). Only completion of tasks on the critical chain move the project forward.

So the question I ask myself is how do I reconcile the need to forecast project performance, while communicating results using flawed, but understood metrics? To further complicate matters, how do I identify the critical chain when my project scheduling software won’t do it for me?

I don’t have answers yet, at least ones I like. I can spend the time identifying the critical chain manually. It might take a lot of paper at first, but once identified I think it would be easy to maintain. From there, I can reorganize my project plan into a critical chain phase and feeder phases, so that I can measure progress in each more easily. Then I need to educate my project leaders on how I’m evaluating project performance, and include the important critical chain progress metric. I think I’ll start there and report later on how it’s working.