Evolution is commonly summarized as “variation plus selection.” That summary is broadly correct, but it can leave a mechanistic gap: it names differential retention, yet it does not always make explicit how durable evolutionary products compound rather than remain isolated local events. TSEET targets that gap by isolating a structural hinge: persistence. If an outcome does not persist, it cannot accumulate. If it persists, it becomes trace. If trace can re-enter, prior outcomes become present determinant conditions that reshape what is reachable next. From that hinge, the remainder follows as an operator chain. Persistence produces trace; trace re-enters; re-entry yields modulation (susceptibility, vectoring, weight); modulation routes viability corridors under coupled multi-scale field interaction (MSFIF); routed corridors bias propagation and retention; retained products become deposits that re-enter again, further reshaping corridors. Major transitions become legible as corridor migration by stepwise viable intermediates, deposit accumulation, and exaptive reuse, while extinction is a boundary outcome when corridor regimes shift beyond what accumulated support tax can sustain.Links (navigation)Landing page: https://armandosotouidt.github.io/tseet/Master index (all theories): https://armandosotouidt.github.io/If links are stripped, search repository: armandosotouidt