Every box explains itself, both ways

The WCLM verdict (it worked) and the next rounds: every chip at every layer clickable, opening its reason-to-be — caused by upstream, feeding downstream, because it's graphs all over. A side pane for the explanations, layer cards for the layers themselves, run-to-run impact made visible (adding one word made a massive difference and the engine should say exactly how much), and example buttons from strong to weak connectivity. Plus the direction: one of these engines at every abstraction jump of the book, rationally explaining each compression.