When to use it
Use it to find demand peaks that a task list conceals.
When to be cautious
A total headcount can hide a scarce skill or equipment conflict.
Apply it
Period demand = Σ effort assigned within that period
Compare demand and usable availability by skill and period. Total project effort can conceal a short local overload.
- Assign effort and resource requirements to scheduled work.
- Aggregate demand by resource and time window.
- Compare with confirmed usable availability and resolve overloads.
An example in practice
Several tasks need the same reviewer in the same week. Their combined demand exceeds capacity even though the overall staffing total seems sufficient.
Source & credit
Common scheduling practice. The critical-path method is associated with James E. Kelley Jr. and Morgan R. Walker; their 1959 paper is the historical reference.
GAO: Schedule Assessment Guide
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