Index: head/en_US.ISO8859-1/books/porters-handbook/special/chapter.xml
===================================================================
--- head/en_US.ISO8859-1/books/porters-handbook/special/chapter.xml
+++ head/en_US.ISO8859-1/books/porters-handbook/special/chapter.xml
@@ -506,14 +506,15 @@
 	their available <acronym>CPU</acronym> power, allowing port
 	builds to be faster and more effective.</para>
 
-      <para>This is achieved by passing <varname>-jX</varname> flag
+      <para>This is achieved by passing <literal>-jX</literal> flag
 	to &man.make.1; running on vendor code.  This is the default
 	build behavior of ports.  Unfortunately, not all ports
 	handle parallel building well and it may be required to
 	explicitly disable this feature by adding the
 	<literal>MAKE_JOBS_UNSAFE=yes</literal> variable.  It is
 	used when a port is known to be broken with
-	<varname>-jX</varname>.</para>
+	<literal>-jX</literal> due to race conditions causing
+	intermittent build failures.</para>
 
       <important>
 	<para>When setting <varname>MAKE_JOBS_UNSAFE</varname>, it