DTM.3:4.5 - Decide whether a fast process may be reduced

If local adjustment is much faster than changes in adoption, a local equilibrium may provide the needed output. First identify the relaxation time and the population-change time over the conditions being compared. Examine startup and interventions, not only a final stationary point.

Retain the local dynamic state when learning delay, fatigue, memory, periodic loading or loss of support changes the prediction. A fast measured response does not establish the absence of slower memory.

The result states what is passed across the boundary, the conditions under which it can be summarized, and the change that would require restoring detail. DTM.4 then investigates persistence and return using that coupled model.