Krugman market-potential field is NON-conserved: over-shares finite surplus into carrying capacity (free lunch)

When coupling a market-access / market-potential field access[i]=Σ_j surplus_j·exp(-cost(i,j)) directly into a settlements carrying capacity as an import term, it double-counts: EVERY deficit node reaches the SAME finite surplus at once, so N nodes each import the full weighted surplus. Measured: 1 producer with surplus 5500, 5 hubs each on a cheap road -> each imports ~0.5*4324=2162, total ~10810 from a 5500 pie. At equilibrium Σconsumption/Σproduction=2.04 — sustained population exceeds total food grown (conservation broken). The fix is a CONSERVED competitive allocation (split each source surplus among bidders ∝ reach·pull, Σnet=0); verified conserved path holds ratio=1.000 exactly. Lesson: a potential measures REACH (non-rival), not ALLOCATION (rival). Never feed a potential straight into capacity; route it. Also watch: an endowment-redirect attr (which resource land yields) honoured in the allocator but IGNORED in the local subsistence term -> a town declared to yield nothing still self-feeds.