In last week’s post, I elaborated on the fixed duration, fixed unit, and fixed work variables for project tasks. I don’t mean to belabor the point, but man, am I having a hard time internalizing this knowledge. Also, while I was talking to Tim Cermak about it, I realized I had a question. (Well, actually, I realized I had about 17 questions, but there’s one in particular that I want to discuss today.)

In talking about fixed duration tasks, Tim said that a really good example of a fixed duration task is pregnancy. He said, “No matter how many doctors or women you add to the duration, ain’t no way that ba is coming out any faster, regardless of effort.”

OK. Yes. As someone who has had five children, I see his point very clearly.

However, while the pregnancy example cleared up the matter of fixed duration, it also raised questions about other fixed variables. I mean, in pregnancy, isn’t the unit (what I was heretofore calling “resource”) also fixed? You can’t share around the tasks of pregnancy among several women. Pregnancy is one woman engaged in the nine-month task of getting that ba safely out of her belly. Believe me, toward the end of each of my pregnancies, if I could have delegated some of the more onerous bits of the pregnancy to other units in order to make it easier or shorter, I would have. But no, I was the only person who could do it. There were no other units to take over. The task was fixed in duration, but the unit (the pregnant lady) was also fixed.

In Dux’s screencast, he stated that you can only have one fixed thing at a time. If the duration is fixed (as in pregnancy), then the work and units are not. And yet, clearly, during pregnancy, both the duration and the units are fixed. As with magnets, you can’t explain that.

Well, said Tim, real-world examples are great to serve as the bases –the foundation– and then there are deltas and deviations from that. As in the case of using pregnancy as an example of a project (or, in this case, a task).

BUT, said Tim, the takeaway from the wrinkle in the pregnancy example, besides the fact that pregnancy is, undeniably, a fixed duration task, is that it shows just how much project management equals change and flexibility, something he told me very early on. Not everything in PM is going to be perfect or work according to a crisp equation. Being a good project manager entails being able to deal with these wrinkles and wrenches when things don’t align in a flawless, textbook sort of way.

He said that, in project management, you identify the basis –call it the baseline– and then track variances to the baseline. With pregnancy, it is one resource (unit, remember) doing the work for a fixed duration. The work may vary as the expectant mother may sleep less or do more work in the nursery or whatever. THEN, you baseline that and tweak accordingly. Theoretically, the duration doesn’t change –the pregnancy will be nine months, plus or minus a couple of weeks on either side for a healthy, typical pregnancy– but some of the other variables DO change. How do those changes affect the outcome? Being able to adapt to those changes and still come out with a satisfactory end result is what project management is all about.

One of my other questions was about whether these scheduling constraints –fixed duration, fixed work, fixed units– are something that Microsoft made up for the Microsoft Project Pro, or if they’re general PM principles. “Ahhhh,” said Tim. “Now we crack open and peek inside Pandora’s Box.”

But that is another topic for another day.