Log real-world road test results and correct/extend the CO-trim theory

New research/ROAD_TEST_LOG.md: the 2026-09-15 flash of
20262-arrow-delete-lowthrottle-composed.hex was a major real-world
success (stalling fully resolved, decel backfire much reduced but not
eliminated). Captures the live diagnostic reasoning that followed:
correcting an overly-lean-leaning framing mid-session (residual decel pop
is more likely a rich-unburned-mixture-with-no-SAI-assist problem, not a
lean one), a structural hypothesis that the Idle Fuel Trim (CO) curve
likely applies whenever the throttle is closed at any RPM rather than
only at a literal stop (only 2 of its 32 points are currently corrected,
and the untouched middle range lines up with the residual pop's RPM
window), and the reasoning for rejecting airbox-baffle removal as a fix
for decel popping specifically (wrong mechanism -- closed throttle isn't
airbox-limited -- and risks worsening the separately-flagged, still
unaddressed main-VE-table leanness gap).

Also updates TABLES.md with the CO-trim applicability open question, and
brings TUNING_GUIDE.md's "local research assets" section up to date (it
still said maps were gitignored/unflashable, both stale).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FP2GaxS9HkUdL5sLBnjKje

tunie/research/TUNING_GUIDE.md

@@ -487,22 +487,27 @@ odometer").** Wrong-generation map IDs that came up and got ruled out:
   variants (`20262`-`20316`), the real SAI/O2 delete map
   (`20188Map2009AIRBOXBONNY.hex`), the America dyno tune
   (`20184dynoTuneSteveO2-Disable.hex`) plus its stock baseline
-  (`20185`/`20186`). Gitignored (`*.hex` at the samplez repo root) — these
-  are working files, not committed, so they won't survive a fresh clone;
-  re-download commands are in each research doc's history if needed again.
-- `reference-maps/derived/` — our own composed candidates (SAI-only,
-  SAI+O2, the trim-composed Arrow variant). **None are known-flashable**
-  — the ECU flash checksum isn't solved (`docs/ROADMAP.md` Phase 3),
-  separate from everything in this document.
+  (`20185`/`20186`). **Committed to the repo as of 2026-09 (`.gitignore`
+  rule removed, explicit user call)** — no longer working-files-only,
+  reachable from a phone browser for TuneECU use.
+- `reference-maps/derived/` — our own composed candidates. **Flashable —
+  the checksum problem is solved** (`reference-maps/checksum.py`, see
+  `docs/ROADMAP.md`). `20262-arrow-delete-lowthrottle-composed.hex` has
+  been flashed on the real bike and road-tested successfully — see
+  `ROAD_TEST_LOG.md` for actual outcomes, not just derivation.
 - `reference-maps/{decode_map,reconstruct_rom,table_map,toggle_devices,
-  compose_arrow_delete}.py` — the working toolchain: decrypt → flat ROM →
-  named tables → device-flag edit → trim-byte compose.
+  compose_arrow_delete,compose_lowthrottle,checksum}.py` — the working
+  toolchain: decrypt → flat ROM → named tables → device-flag edit →
+  trim-byte compose → low-throttle table compose → checksum patch.
 - `tuneecu_site_mirror/` — full local mirror of tuneecu.net's
   documentation (built by `tuneecu_crawl.py`), including the German
   road-tuning primer. The live site says it won't be updated after
   September 2024 — this mirror is insurance against link rot.
 - `PERMUTATIONS.md`, `TABLES.md`, `DEVICES.md`, `COMMUNITY_TUNING.md` — the
-  detailed research trail; this file is the index, those are the evidence.
+  detailed research trail (how the ROM format works); this file is the
+  index. **`ROAD_TEST_LOG.md`** — the separate, real-world log: what
+  actually happened flashing and riding on it, distinct from derived facts
+  about the ROM.
 
 ## Open questions, if this gets picked up again