The Concept AXN begins from a measured defect: seven editions of one work carried one backward pointer and zero forward pointers, so a reader arriving at the edition a search engine is most likely to hold had no route to the current state.
Forward-pointing every prior edition on each bump is O(n) per version and conflicts with content-addressing: editing a published edition either changes its hash or puts the pointer outside the hashed content, where a copy of the deposit does not carry it.
Reframed before deposit, and the reframing is the point. This is not a new identifier type. The LABOR canonical invariant already specifies AXN root = stable work relation beside AXN version = immutable version relation, and the AXN protocol now carries that at identity_semantics. What is missing is narrower and is recorded there as a known_gap: root_axn is composed from the per-deposit hex and is therefore not stable across editions. Two editions of one work carry different roots today.
Read as an implementation proposal for an existing invariant, with the derivation left open — whether a stable root is derived from the work identifier or allocated with the first edition.