diff --git a/Documentation/pretty-options.txt b/Documentation/pretty-options.txt
index 74aa01a..642af6e 100644
--- a/Documentation/pretty-options.txt
+++ b/Documentation/pretty-options.txt
@@ -37,7 +37,10 @@
 	in their encoding header; this option can be used to tell the
 	command to re-code the commit log message in the encoding
 	preferred by the user.  For non plumbing commands this
-	defaults to UTF-8.
+	defaults to UTF-8. Note that if an object claims to be encoded
+	in `X` and we are outputting in `X`, we will output the object
+	verbatim; this means that invalid sequences in the original
+	commit may be copied to the output.
 
 --notes[=<ref>]::
 	Show the notes (see linkgit:git-notes[1]) that annotate the