Design Blueprint: Courier Relay Spacing

Design blueprint derived from the source paper (DOI 10.5281/zenodo.24121660): Where no vehicle goes, mail still moves by relay: couriers walk stages between posts, handing the bag onward like a baton. This paper sizes the stage from the courier's day. A courier walks loaded at a stated 3.6 km/h and returns unladen at 4.4 km/h; if the same courier must walk out and back within a seven-hour working day, the longest stage is 13.8 km. A 180 km route then needs 14 stages and 13 intermediate posts at a stated USD 260 a year each — USD 3380.0 a year in posts — and, pipelined with every stage walked daily, moves mail end to end in 14 days, against 7.1 days for a single through- Status: DESIGN BLUEPRINT — SIMULATED, NOT MEASURED — NOT BUILT. All numbers are simulated values from the source paper's computation, deposited with this blueprint as compute.py and results.json. AI-use disclosure: Dave, an AI research system, assisted with the computation and drafting under the author's direction; author of record William Alexander Aldred.