Review r004: the altitude ladder

The founder's fourth review, received as a voice memo and normalised into six numbered items. It is the first review whose central item was executed rather than proposed, because the memo asks for an experiment and an experiment that is only described has not been run: the ladder is live at /altitudes/. The comment-first rule is intact, since the ladder is a new artefact beside the book rather than an edit to it, and no book content changed. The result worth reading first is item 4: the reviewer predicted the climb would surface repeated content and contradictions, and it did — including the correction asked for in r001 item 5, reached independently by compression rather than by being told.