Move Responsibilities ★

Moving responsibilities among roles is a delicate balancing act.

...you want to change the communication patterns of the organization as a whole, not in a way that depends on a specific role, but in a way that optimizes the effectiveness of communication of an entire organization.

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Unscrutinized relationships between roles can lead to poor overall patterns of coupling in the greater organization.

In the spirit of ConwaysLaw, organizations tend to form around loci of communication; that is, the roles tend to communicate chiefly with each other, rather than to other (small) organizations in the larger enterprise. But some roles find themselves pulled in two different directions: they have substantial communication needs outside the organization.

You want cohesive roles. And you want cohesive organizations. De-coupled organizations are more important than cohesive roles. And there may be fundamental trade-offs between coupling and cohesion. Moving an entire role from one process or organization to another doesn't reduce the overall coupling, but only moves the source. You could move a person from one organization to another organization to make things more balanced, but responsibilities don't always align with individuals. You could replicate responsibilities across multiple roles or organizations to increase locality; however, that tends to confuse ownership and coordination, and is not guaranteed to decrease the coupling, anyway.

Therefore:

Move responsibilities from the role that creates the most undesirable coupling, to the roles coupled to it from other processes. Simply said, this is load balancing. The responsibilities should not be shifted arbitrarily; a chief programmer team organization is one good way to implement this pattern (in the context for Developer role responsibilities).

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The new process may exhibit more highly de-coupled groups. It is important to balance group cohesion with the de-coupling, so this pattern must be applied with care. For example, the Developer role is often the locus of a large fraction of project responsibilities, so the role appears overloaded. Arbitrarily shifting Developer responsibilities to other roles can introduce communication overhead. A chief programmer team approach to the solution helps balance these forces.

HallwayChatter is an alternative load-balancing pattern; ResponsibilitiesEngage can be seen as a refinement of this pattern that evens load. UpsideDownMatrixManagement is a refinement of this pattern that's particularly applicable across enterprise boundaries.

Most of the design rationale follows from the forces themselves.

This is isomorphic to Mackenzie's model that task interdependencies, together with the interdependencies of task resources and their characteristics, define project roles [BibRef-Mackenzie1986].

This organization can be improved by redistributing some of the responsibilities of Tester at the bottom center.