diff --git a/game/reconstructed/dmgtable.cpp b/game/reconstructed/dmgtable.cpp
index a61ec11..a685644 100644
--- a/game/reconstructed/dmgtable.cpp
+++ b/game/reconstructed/dmgtable.cpp
@@ -175,6 +175,7 @@ DamageZonePercentTable *
 {
 	if (sliceCount <= 0)	return 0;
 
+	Scalar thetaIn = theta;
 	if (rotateWithTorso)								// binary this[3] != 0
 	{
 		// #124 frame adapter, angular half: theta arrives in the 1995 frame
@@ -189,6 +190,19 @@ DamageZonePercentTable *
 	int index = (int)floorf(theta * (Scalar)sliceCount * (1.0f / TwoPi));
 	if (index < 0)					index = 0;
 	if (index > sliceCount - 1)		index = sliceCount - 1;
+
+	// #124 twist-sign bench: expose the twist term itself -- the leaf is a
+	// weighted roll, so the SLICE choice (not the rolled zone) is the signal.
+	if (getenv("BT_DMGTABLE_LOG"))
+	{
+		static int s_sl = 0;
+		if (s_sl++ < 400)
+			DEBUG_STREAM << "[slice] rot=" << (int)rotateWithTorso
+				<< " twist=" << (float)owner->TorsoHeading()
+				<< " thetaIn=" << (float)thetaIn
+				<< " thetaAdj=" << (float)theta
+				<< " -> slice " << index << "/" << sliceCount << std::endl;
+	}
 	return slices[index];
 }
 
@@ -327,6 +341,12 @@ int
 	{
 		static int s_rh = 0;
 		if (s_rh++ < 400)
+		{
+			extern int BTMechZoneSegAndName(void *mech_v, int zone_idx,
+				int *seg_out, const char **name_out);
+			int seg = -1; const char *zname = 0;
+			if (resolved >= 0)
+				BTMechZoneSegAndName((void *)owner, resolved, &seg, &zname);
 			DEBUG_STREAM << "[dmgresolve] impact=(" << impact.x << ","
 				<< impact.y << "," << impact.z << ")"
 				<< " local=(" << local.x << "," << local.y << "," << local.z << ")"
@@ -334,7 +354,9 @@ int
 				<< " frac=" << (depth / heightRef)
 				<< " layer=" << layerIndex << "/" << layerCount
 				<< " theta=" << theta
-				<< " -> zone " << resolved << std::endl;
+				<< " -> zone " << resolved
+				<< " '" << (zname ? zname : "?") << "'" << std::endl;
+		}
 	}
 	return resolved;
 }
diff --git a/game/reconstructed/mech4.cpp b/game/reconstructed/mech4.cpp
index 1447c0e..1023d4a 100644
--- a/game/reconstructed/mech4.cpp
+++ b/game/reconstructed/mech4.cpp
@@ -3384,6 +3384,34 @@ void
 						}
 						sPrevXT = xtNow;
 						gBTTwistAxis = sTwist;
+						// DIAG (BT_FORCE_TWIST=<-1..1>): pin the twist axis for
+						// the #124 twist-sign bench (the axis is a RATE demand,
+						// so a pinned axis slews the torso to its per-mech
+						// LIMIT and holds -- a known, stable twist state).
+						// Same pattern as BT_FORCE_ELEV below.
+						{
+							static float s_ft = -2.0f;
+							if (s_ft < -1.5f)
+							{
+								const char *ft = getenv("BT_FORCE_TWIST");
+								s_ft = ft ? (float)atof(ft) : -3.0f;
+							}
+							if (s_ft >= -1.0f)
+							{
+								gBTTwistAxis = s_ft;
+								// BASIC mode ignores the twist axis (the stick
+								// steers the legs; the torso auto-centers), so
+								// the pin also cycles the control mode ONCE:
+								// Basic -> Standard puts the mapper's twist
+								// branch in charge.
+								static int s_ftMode = 0;
+								if (!s_ftMode)
+								{
+									s_ftMode = 1;
+									gBTModeCycle = 1;
+								}
+							}
+						}
 
 						// TORSO ELEVATION (pitch aim -- the pod stick's Y
 						// axis; every 1995 control mode routes it to
diff --git a/game/reconstructed/mechmppr.cpp b/game/reconstructed/mechmppr.cpp
index e8e5773..985ef5d 100644
--- a/game/reconstructed/mechmppr.cpp
+++ b/game/reconstructed/mechmppr.cpp
@@ -840,6 +840,15 @@ void
 					extern float gBTElevAxis;
 					stickPosition.y = gBTElevAxis;
 				}
+				// #124 twist-sign bench probe: is the axis routed, and in what mode?
+				if (getenv("BT_TORSO_LOG"))
+				{
+					static int s_mp = 0;
+					if ((s_mp++ % 60) == 0 && s_mp < 1200)
+						DEBUG_STREAM << "[mppr] mode=" << (int)controlMode
+							<< " twistAxis=" << gBTTwistAxis
+							<< " keyTurn=" << key_turn << "\n" << std::flush;
+				}
 				if (controlMode == BasicMode)
 				{
 					stickPosition.x = key_turn;
diff --git a/game/reconstructed/torso.cpp b/game/reconstructed/torso.cpp
index f95de2b4..fc77c2a 100644
--- a/game/reconstructed/torso.cpp
+++ b/game/reconstructed/torso.cpp
@@ -587,6 +587,23 @@ void
 		static int s_sweep = 0;
 		analogTwistAxis = ((++s_sweep / 90) & 1) ? -1.0f : 1.0f;	// +/- every ~90 frames
 	}
+	// #124 twist-sign bench (BT_FORCE_TWIST=<-1..1>): HOLD the analog axis at a
+	// constant (the sweep above alternates) -- the sim integrates currentTwist
+	// to the per-mech limit and stays, giving the cylinder-table bench a known
+	// twist state at the SIM level, independent of the input plumbing.
+	{
+		static float s_forceTwist = -2.0f;
+		if (s_forceTwist < -1.5f)
+		{
+			const char *ft = getenv("BT_FORCE_TWIST");
+			s_forceTwist = ft ? (float)atof(ft) : -3.0f;
+		}
+		if (s_forceTwist >= -1.0f)
+		{
+			effectiveTwistRate = baseTwistRate;
+			analogTwistAxis = s_forceTwist;
+		}
+	}
 
 	// TORSO GATE PROBE (BT_TORSO_LOG): why is the twist rate zero?
 	if (getenv("BT_TORSO_LOG"))
diff --git a/scratchpad/night11/twistsign.sh b/scratchpad/night11/twistsign.sh
new file mode 100644
index 0000000..9893310
--- /dev/null
+++ b/scratchpad/night11/twistsign.sh
@@ -0,0 +1,45 @@
+#!/usr/bin/env bash
+# #124 TWIST-SIGN VERIFY -- the follow-up the frame-adapter work left open:
+# SelectSlice's torso-twist term sign was INFERRED from the z-negation
+# reflection, never exercised (every probe ran at twist 0).  Rig: stationary
+# madcat TARGET pinned at full twist (BT_FORCE_TWIST, rate-demand axis ->
+# slews to the per-mech limit and holds), shooter approaches to a fixed
+# bearing and pulses LRM salvos (BT_AF_MISSILE -- missiles are the authentic
+# cylinder-path weapon; beams with zone -1 were DROPPED by the binary).
+# Two configs: twist +1 vs -1.  READ: target's [dmgresolve] zone spread --
+# hull-fixed wheels (legs/hip) must NOT move between runs (control); torso
+# wheels must swap L/R families to match the flank visibly facing the
+# shooter (A's BT_SHOT captures are the ground truth).
+set -x
+. /c/git/bt411/scratchpad/night6/bench_common.sh
+cd /c/git/bt411/content || exit 1
+bt_assert_player_env
+
+for TW in 0 +1 -1; do
+  TAG=Z; [ "$TW" = "+1" ] && TAG=P; [ "$TW" = "-1" ] && TAG=N
+  taskkill //F //IM btl4.exe > /dev/null 2>&1
+  sleep 2
+  rm -f ts_${TAG}_a.log ts_${TAG}_b.log ts${TAG}_*.png
+  bt_expert_egg MP.EGG TS.EGG
+  sed -i "s/^map=.*/map=grass/; s/^time=.*/time=day/; s/^vehicle=.*/vehicle=madcat/" TS.EGG
+
+  # TARGET: stationary, torso pinned; log every cylinder resolution.
+  BT_FORCE_TWIST=$TW BT_DMGTABLE_LOG=1 BT_CYL_LOG=1 BT_DMG_LOG=1 BT_MP_LOG=1 \
+    bt_launch ts_${TAG}_b.log TS.EGG 0x0C -net 1601
+  sleep 2
+  # SHOOTER: approach to fixed range, missile salvos only, periodic captures.
+  BT_GOTO=enemy BT_GOTO_STOP=90 BT_KEY_NOFOCUS=1 \
+  BT_AF_MISSILE=1 BT_AF_PERIOD=6 \
+  BT_DMG_LOG=1 BT_MP_LOG=1 BT_SHOT_EVERY=300 BT_SHOT_PREFIX=ts$TAG \
+    bt_launch ts_${TAG}_a.log TS.EGG 0x03 -net 1501
+  sleep 5
+  python ../tools/btconsole.py TS.EGG 127.0.0.1:1501 127.0.0.1:1601 \
+    > ts_${TAG}_relay.log 2>&1 &
+  RELAY=$!
+  sleep 170
+  kill $RELAY 2>/dev/null
+  taskkill //F //IM btl4.exe > /dev/null 2>&1
+  sleep 3
+done
+echo "=== resolves per run:"
+grep -c dmgresolve ts_Z_b.log ts_P_b.log ts_N_b.log