Topology

The prior art (Brelsford, Martin & Bettencourt): it gives every parcel a road frontage with as little new road as it can, repeatedly connecting the deepest parcels to the road network by short paths along parcel boundaries. It is practical only on small blocks: at each step it considers every short candidate path around the deepest parcels, and that grows steeply with block size, so a single run can take hours on a block of several hundred parcels. That is why it appears in the single-block flagship and nowhere else, and why that flagship exists at all.

Configuration: conf/method/topology.yaml

Head-to-head on one deep block

From the method-comparison example: six reblockers on ZAF.9.3.1_1_40972, the deepest topology-tractable block in the Cape Town metro (263 parcels, up to 7 rings deep), graded on permeability (a flow measure of how easily every parcel can reach a street) against displacement.

At this method's full build-out on that block (terminal point of its permeability-vs-displacement frontier):

homes displaced	permeability
51.4%	97.7%