diff --git a/Documentation/rerere-options.txt b/Documentation/rerere-options.txt
index 8f4849e272..c3321ddea2 100644
--- a/Documentation/rerere-options.txt
+++ b/Documentation/rerere-options.txt
@@ -1,4 +1,9 @@
 --rerere-autoupdate::
 --no-rerere-autoupdate::
-	Allow the rerere mechanism to update the index with the
-	result of auto-conflict resolution if possible.
+	After the rerere mechanism reuses a recorded resolution on
+	the current conflict to update the files in the working
+	tree, allow it to also update the index with the result of
+	resolution.  `--no-rerere-autoupdate` is a good way to
+	double-check what `rerere` did and catch potential
+	mismerges, before committing the result to the index with a
+	separate `git add`.