diff --git a/c/glm.c b/c/glm.c
index 7f2d491..bbebd81 100644
--- a/c/glm.c
+++ b/c/glm.c
@@ -392,8 +392,12 @@ static void matmul_i4_pair(float *yg, float *yu, const float *x,
 }
 
 static void matmul_qt(float *y,const float *x,QT *w,int S);
+static int g_no_fused_pair=0;  /* COLI_NO_FUSED_PAIR=1: disable the gate+up kernel fusion
+ * that changes OMP scheduling vs separate matmul_qt calls — this
+ * shifts floating-point accumulation order and can collapse MTP
+ * draft acceptance by flipping near-ties (#163). */
 static void expert_gate_up(float *g,float *u,const float *x,QT *wg,QT *wu,int S){
-    if(S==1&&wg->fmt==2&&wu->fmt==2&&wg->I==wu->I&&wg->O==wu->O)
+    if(!g_no_fused_pair&&S==1&&wg->fmt==2&&wu->fmt==2&&wg->I==wu->I&&wg->O==wu->O)
         matmul_i4_pair(g,u,x,wg->q4,wg->s,wu->q4,wu->s,wg->I,wg->O);
     else { matmul_qt(g,x,wg,S); matmul_qt(u,x,wu,S); }
 }
@@ -3667,7 +3671,8 @@ int main(int argc, char **argv){
      * re-exec + tuning path (distinct from the internal COLI_OMP_TUNED sentinel).
      *
      * Must remain the FIRST statement in main(): argv is passed verbatim to execv(). */
-    if(!getenv("COLI_OMP_TUNED") && !getenv("COLI_NO_OMP_TUNE")){
+    if(!getenv("COLI_OMP_TUNED") && !getenv("COLI_NO_OMP_TUNE") &&
+       !getenv("COLI_CUDA") && !getenv("COLI_METAL")){
         setenv("OMP_WAIT_POLICY","active",0);  /* keep the team hot across the tiny per-expert matmul regions */
         setenv("GOMP_SPINCOUNT","200000",0);   /* spin briefly, then yield so long disk waits don't burn a core */
         setenv("OMP_PROC_BIND","close",0);     /* pack the team onto adjacent cores for cache locality */
@@ -3704,7 +3709,8 @@ int main(int argc, char **argv){
     }
     g_mlock  = getenv("MLOCK")?atoi(getenv("MLOCK")):-1;   /* -1 auto (ON macOS), 0 off, 1 force / auto (ON macOS), 0 off, 1 force */
     g_spec = getenv("SPEC")?atoi(getenv("SPEC")):1;
-    g_draft = getenv("DRAFT")?atoi(getenv("DRAFT")):-1;   /* -1 = auto: 3 se MTP, 0 senza */
+    g_draft = getenv("DRAFT")?atoi(getenv("DRAFT")):-1;
+    g_no_fused_pair = getenv("COLI_NO_FUSED_PAIR")?atoi(getenv("COLI_NO_FUSED_PAIR")):0;   /* -1 = auto: 3 se MTP, 0 senza */
     g_looka = getenv("LOOKA")?atoi(getenv("LOOKA")):0;    /* 1 = misura predicibilita' routing */
     g_pilot = getenv("PILOT")?atoi(getenv("PILOT")):0;    /* 1 = prefetch pilotato dal router */
     g_pilot_real = getenv("PILOT_REAL")?atoi(getenv("PILOT_REAL")):0; /* default OFF: load VERI cross-layer (value-preserving prefetch); PILOT_REAL=1 opta in */