D31 — --component-rules off by default for placement and routing

Superseded by D52

Decision

--component-rules defaults to off for both tracemaker-place and tracemaker route; soft is opt-in

Alternatives

Default soft (doc 15 §3.5 planned it once the §9 gates pass)

Reason

Measured on the 23-board placement set, 9 ESD boards and 6 boards × 3 seeds (doc 15 §14.3): soft brings crystals 6.4 → 5.1 mm, ESD parts 7.1 → 3.2 mm and load caps closer at equal HPWL, but decoupling and regulator caps move away on some boards (decaps worse on 9 of 18 runs); doubling the decap ties fixes that for +2–3 % HPWL. Held-out detection recall for USB connectors, connectors and mounting holes is below the 0.8 gate. off reproduces the previous output byte for byte