This essay will interest software development managers who want an empirical test of Frederick Brooks’s famous “law” that adding staff to a late software project makes it later [1]. Abdel-Hamid seems to have hit on a nice idea: we have tended to accept Brooks’s assertion as being intuitively obvious, even if initially paradoxical. No one bothered to do any empirical research until Abdel-Hamid saw an opportunity.

The author deploys an elaborate model of the software development process that includes subsystems for human resources management, software production, controlling, and planning. The first of these subsystems receives most of the attention. One crucial factor, “willingness to change workforce” (e.g., add to it toward the end of the project as staff attrition increases), can be combined with a “maximum tolerable completion date” to account for the seemingly self-destructive staffing behavior that occurs in some projects. Managers, who are willing to pay any price to keep the schedule from slipping when the critical path lies through completed software, gamble that the net impact of adding more people to a late project will not be negative (i.e., it will not cause the schedule to slip further).

Citing evidence from a NASA case study and computer simulations based on his own model, the author concludes, “adding more people to a late project always causes it to become more costly, but does not always cause it to complete later.” The mythical man-month is less mythical than we believed.

The author accepts Brooks’s basic insight that time and staff are not mutually substitutable (because of the overhead represented by the exponentially multiplying communication and political interfaces). He deploys a number of factors (including “willingness to change workforce”) to show that an equivalence exists but is not one-for-one. While readers are invited to form their own conclusions, I do not think we need to rush to Brooks’s defense, nor is he here conclusively refuted. Still, we should be thankful to Abdel-Hamid for unpacking the deep structure of Brooks’s law, which, as originally stated, is as much a slogan as an axiom.