diff --git a/collects/scheme/private/class-internal.ss b/collects/scheme/private/class-internal.ss
index 97c9927d5d..f970efd1d9 100644
--- a/collects/scheme/private/class-internal.ss
+++ b/collects/scheme/private/class-internal.ss
@@ -2402,22 +2402,21 @@
     (define method-ht (class-method-ht cls))
     (define beta-methods (class-beta-methods cls))
     (define meth-flags (class-meth-flags cls))
-    (define (check-overrideable m)
-      (let ([index (hash-ref method-ht m #f)])
-        (unless index
-          (failed "no public method ~a" m))
-        (let ([flag (vector-ref meth-flags index)])
-          (when (eq? flag 'final)
-            (failed "method ~a is final, not overrideable" m))
-          (when (eq? flag 'augmentable)
-            (failed "method ~a is augmentable, not overrideable" m)))))
     (unless (class? cls)
       (failed "not a class"))
     (for ([m (class/c-methods ctc)])
       (unless (hash-ref method-ht m #f)
         (failed "no public method ~a" m)))
     (for ([m (class/c-overrides ctc)])
-      (check-overrideable m))
+      (let ([index (hash-ref method-ht m #f)])
+        (unless index
+          (failed "no public method ~a" m))
+        (let ([vec (vector-ref beta-methods index)])
+          (unless (zero? (vector-length vec))
+            (failed "method ~a was previously augmentable" m)))
+        (let ([flag (vector-ref meth-flags index)])
+          (when (eq? flag 'final)
+            (failed "method ~a is final, not overrideable" m)))))
     (for ([m (class/c-augments ctc)])
       (let ([index (hash-ref method-ht m #f)])
         (unless index
@@ -2426,7 +2425,14 @@
           (when (zero? (vector-length vec))
             (failed "method ~a has never been augmentable" m)))))
     (for ([s (class/c-supers ctc)])
-      (check-overrideable s))
+      (let ([index (hash-ref method-ht s #f)])
+        (unless index
+          (failed "no public method ~a" s))
+        (let ([flag (vector-ref meth-flags index)])
+          (when (eq? flag 'final)
+            (failed "method ~a is final, not overrideable" s))
+          (when (eq? flag 'augmentable)
+            (failed "method ~a is augmentable, not overrideable" s)))))
     (for ([i (class/c-inners ctc)])
       (let ([index (hash-ref method-ht i #f)])
         (unless index