diff --git a/x/installing/tuning-fontconfig.xml b/x/installing/tuning-fontconfig.xml
index e2ddbd0905..530119d42f 100644
--- a/x/installing/tuning-fontconfig.xml
+++ b/x/installing/tuning-fontconfig.xml
@@ -420,7 +420,7 @@ cat > ~/.config/fontconfig/fonts.conf << "EOF"
     hintfull: is supposed to give a crisp font that aligns well to the
     character-cell grid but at the cost of its proper shape.
 
-    hintmedium: poorly documented, maybe a synonym for hintfull.
+    hintmedium: is reported to be broken.
     hintslight is the default: - supposed to be more fuzzy but retains shape.
 
     hintnone: seems to turn hinting off.
@@ -442,9 +442,25 @@ cat > ~/.config/fontconfig/fonts.conf << "EOF"
 EOF</userinput></screen>
 
     <para>
-      You will now need to edit the file in your preferred editor.
+      You will now need to edit the file in your preferred editor. Many of the
+      different settings give very subtle differences and the results may differ
+      for some of the fonts you use.
     </para>
 
+    <note>
+      <para>
+        Hinting, if enabled, is done in <application>FreeType</application>.
+        Since FreeType-2.7 the default TrueType interpreter is v40. The
+        original v35 hinter could be enabled by an environment variable, but
+        is only really appropriate to original Microsoft TTF fonts (Arial, etc).
+        The v38 hinter (Infinality) is not built by default and all the options
+        to tune it have been removed. For full details see <xref
+        linkend="subpixel-hinting"/> (Spoiler: there is NO sub-pixel hinting,
+        the code simply ignores <emphasis>all</emphasis> horizontal hinting
+        instructions.
+      </para>
+    </note>
+
     <para>
       For more examples see the blfs-support thread which started at <ulink
       url="https://lists.linuxfromscratch.org/sympa/arc/blfs-support/2016-09/msg00128.html">2016-09/00128</ulink>,
@@ -844,6 +860,16 @@ EOF</userinput></screen>
       non-MS Japanese fonts when an ugly MS font is already installed.
     </para>
 
+    <bridgehead renderas="sect3" id="subpixel-hinting"
+    xreflabel="subpixel-hinting">subpixel-hinting</bridgehead>
+
+    <para>The documentation of the FreeType v40 interpreter at <ulink
+      url="https://freetype.org/freetype2/docs/hinting/subpixel-hinting.html">freetype
+      docs</ulink>
+      explains how the current hinter works, and why the previous (slow) Infinality
+      interpreter was replaced.
+    </para>
+
     <bridgehead renderas="sect3" id="arch-fontconfig"
     xreflabel="Fontconfig in the Arch wiki">Fontconfig in the Arch wiki</bridgehead>