diff --git a/doc/xmllint.xml b/doc/xmllint.xml
index 547bf678..3de2b875 100644
--- a/doc/xmllint.xml
+++ b/doc/xmllint.xml
@@ -283,6 +283,10 @@
                     environment variable controls the indentation. The default value is two
                     spaces "  ").
                 </para>
+                <para>
+                    Especially in the absence of a DTD, this feature has never worked reliably
+                    and is fundamentally broken.
+                </para>
             </listitem>
         </varlistentry>
 
diff --git a/parser.c b/parser.c
index ccfa9e53..3e034d47 100644
--- a/parser.c
+++ b/parser.c
@@ -4914,6 +4914,11 @@ get_more_space:
                     (ctxt->disableSAX == 0) &&
                     (ctxt->sax->ignorableWhitespace !=
                      ctxt->sax->characters)) {
+                    /*
+                     * Calling areBlanks with only parts of a text node
+                     * is fundamentally broken, making the NOBLANKS option
+                     * essentially unusable.
+                     */
                     if (areBlanks(ctxt, tmp, nbchar, 1)) {
                         if (ctxt->sax->ignorableWhitespace != NULL)
                             ctxt->sax->ignorableWhitespace(ctxt->userData,
@@ -13715,11 +13720,9 @@ xmlCtxtSetOptionsInternal(xmlParserCtxtPtr ctxt, int options, int keepMask)
  *
  * XML_PARSE_NOBLANKS
  *
- * Remove some text nodes containing only whitespace from the
- * result document. Which nodes are removed depends on DTD
- * element declarations or a conservative heuristic. The
- * reindenting feature of the serialization code relies on this
- * option to be set when parsing. Use of this option is
+ * Remove some whitespace from the result document. Where to
+ * remove whitespace depends on DTD element declarations or a
+ * broken heuristic with unfixable bugs. Use of this option is
  * DISCOURAGED.
  *
  * Not supported by the push parser.