diff --git a/doc/bugs/smudge_filter_drastically_slows_down_git_diff.mdwn b/doc/bugs/smudge_filter_drastically_slows_down_git_diff.mdwn
index 7f05e76bdf..3899d18fd8 100644
--- a/doc/bugs/smudge_filter_drastically_slows_down_git_diff.mdwn
+++ b/doc/bugs/smudge_filter_drastically_slows_down_git_diff.mdwn
@@ -114,3 +114,5 @@ Running on openSUSE Tumbleweed.
 ### Have you had any luck using git-annex before? (Sometimes we get tired of reading bug reports all day and a lil' positive end note does wonders)
 
 Yes, mostly a happy user ;-)
+
+> [[dup|done]]
diff --git a/doc/bugs/smudge_filter_drastically_slows_down_git_diff/comment_2_98cdd89081d2f31a45b693a04b20f345._comment b/doc/bugs/smudge_filter_drastically_slows_down_git_diff/comment_2_98cdd89081d2f31a45b693a04b20f345._comment
new file mode 100644
index 0000000000..9f35e654f5
--- /dev/null
+++ b/doc/bugs/smudge_filter_drastically_slows_down_git_diff/comment_2_98cdd89081d2f31a45b693a04b20f345._comment
@@ -0,0 +1,15 @@
+[[!comment format=mdwn
+ username="joey"
+ subject="""comment 2"""
+ date="2020-07-21T14:00:05Z"
+ content="""
+This is exactly what that todo is about. I'm going to close this as a dup.
+
+I suppose git diff runs it twice because it's smudging both sides of the diff.
+
+Note that git status does not re-run the smudge filter on the same file
+repeatedly (at least most of the time), so the overhead there is only one
+run per modification of a file. Unfortunately git diff does not benefit from
+such caching. Still, it only runs once per modified file in the repo,
+not on unmodified files.
+"""]]