diff --git a/src/applications/differential/field/DifferentialTestPlanCommitMessageField.php b/src/applications/differential/field/DifferentialTestPlanCommitMessageField.php
--- a/src/applications/differential/field/DifferentialTestPlanCommitMessageField.php
+++ b/src/applications/differential/field/DifferentialTestPlanCommitMessageField.php
@@ -50,11 +50,4 @@
     );
   }
 
-  public function validateTransactions($object, array $xactions) {
-    return $this->validateCommitMessageCorpusTransactions(
-      $object,
-      $xactions,
-      pht('Test Plan'));
-  }
-
 }
diff --git a/src/applications/differential/xaction/DifferentialRevisionTestPlanTransaction.php b/src/applications/differential/xaction/DifferentialRevisionTestPlanTransaction.php
--- a/src/applications/differential/xaction/DifferentialRevisionTestPlanTransaction.php
+++ b/src/applications/differential/xaction/DifferentialRevisionTestPlanTransaction.php
@@ -55,7 +55,10 @@
   }
 
   public function validateTransactions($object, array $xactions) {
-    $errors = array();
+    $errors = $this->validateCommitMessageCorpusTransactions(
+      $object,
+      $xactions,
+      pht('Test Plan'));
 
     $is_required = PhabricatorEnv::getEnvConfig(
       'differential.require-test-plan-field');