An adaptive set bound to a scalar value (ASet.bind, PLAN.md Section 7.4): mapping value selects the inner set; when the value changes, the whole inner set is swapped (old content removed, new content added) and the old inner sink is unregistered eagerly (FDA BindReader semantics; ANALYSIS-FDA.md Pitfall 1). The inner set's own changes flow through a journal. Registration is lazy (first read); disposal unregisters everything.