CMP.10:4.5 - Compare alternatives at the receiving use

Construct the simplest credible alternative, not only a slower version of the favored structure. Compare raw storage with a precomputed index, full retention with reconstruction, or a compact representation with an expanded one according to the actual operations.

Require preservation of the needed answers before treating reduced cost as improvement. For a deliberate approximation, retain its qualified result and the loss it buys. Use the existing characterization, Pareto and improvement methods when choices trade storage, latency, update work and precision; no single representation must dominate every workload.

Select conversion only when its cost and risk are justified by the expected subsequent use. A mixed strategy can keep a simple base representation and add one index for the consequential query. Its update obligations remain part of the choice.