A lot of </para> tags have leading whitespace before them. Remove it. Do
this (in Emacs) by searching for

\s-+</para>

and replacing with

</para>

Do this for all occurences *except* where the element immediately before
the </para> is one of <itemizedlist>, <orderedlist>, <variablelist>,
<procedure>. The <para>...</para> wrapping these elements is mostly
redundant, and will be removed later.