diff --git a/tests/bench/mvcgen/sym/vcgen_get_throw_set_grind.lean b/tests/bench/mvcgen/sym/vcgen_get_throw_set_grind.lean
index ceee64a96d..bcebf50ec7 100644
--- a/tests/bench/mvcgen/sym/vcgen_get_throw_set_grind.lean
+++ b/tests/bench/mvcgen/sym/vcgen_get_throw_set_grind.lean
@@ -15,5 +15,7 @@ set_option maxHeartbeats 100000000
 
 -- Benchmark `mvcgen' with grind`: grind integrated into VCGen loop for incremental
 -- context internalization. This avoids O(n) re-internalization per VC.
-#eval runBenchUsingTactic ``GetThrowSetGrind.Goal [``loop, ``step] `(tactic| mvcgen' with grind) `(tactic| fail)
+-- `simplifying_assumptions [Nat.add_assoc]` here speeds up grind and kernel checking by a factor
+-- of 2 because long chains `s + 1 + ... + 1` are collapsed into `s + n`.
+#eval runBenchUsingTactic ``GetThrowSetGrind.Goal [``loop, ``step] `(tactic| mvcgen' simplifying_assumptions [Nat.add_assoc] with grind) `(tactic| fail)
   [50, 100, 150]