D63 — Half-pitch variant for small boards, no gridless arm

Decision

One portfolio variant (cheap vias) routes small boards at half the lattice pitch; no gridless arm is built

Alternatives

A gridless tile-plane router as a portfolio arm

Reason

Half pitch at four times the work: 4,140 → 4,153 routed on 12 nearly clean boards, one more complete. As a variant: tier B 27 → 28 clean, tier C equal, routed +7 and +8, no added errors (doc 05 §25)