D126 — Four opt-in escape features from the EtherCAT review

Decision

Four opt-in escape features from the EtherCAT shield review: --escape-length, --escape-persist, --radial-supply, --via-drops (doc 05 §47)

Alternatives

One bundle router with planar order and layer assignment (not built); a finer lattice and part moves (the review measured them to do nothing)

Reason and results

Each is a small change on the existing escape plan, planner or endpoint code and cannot add a violation (every commit is still checked exactly); measured: EtherCAT 177 -> 185 of 207 routed, other boards neutral to slightly negative, so all stay off by default