Fix double word in doc of latex_table_style, improve it

doc/usage/configuration.rst

@@ -2261,32 +2261,34 @@ These options influence LaTeX output.
    If using ``'booktabs'`` or ``'borderless'`` it seems recommended to also
    opt for ``'colorrows'``...
 
-   Each table can be styled in a way overriding the global setting, if
-   assigned classes (via ``:class:`` or ``.. rst-class::``, see
-   :ref:`table-directives`) among the following list: ``booktabs``,
-   ``borderless``, ``standard``, ``colorrows``, ``nocolorrows``.  Using
-   ``standard`` means to render tables in the standard LaTeX way with both
-   horizontal and vertical lines and has no influence on colour status.
+   Each table can override the global style via ``:class:`` table directive
+   option, or ``.. rst-class::`` for no-directive table (cf.
+   :ref:`table-directives`).  Currently recognized classes are ``booktabs``,
+   ``borderless``, ``standard``, ``colorrows``, ``nocolorrows``.  The latter
+   two can be combined with any of the first three.  The ``standard`` class
+   produces tables with both horizontal and vertical lines (as has been the
+   default so far with Sphinx).
 
-   Merged contiguous cells located on a single row row will obey correctly the
-   row colour, if set.
+   A single-row multi-column merged cell will obey the row colour, if it is
+   set.
 
    .. note::
 
       - It is hard-coded in LaTeX that a single cell will obey the row colour
         even if there is a column colour set via ``\columncolor`` from a custom
-        table column specification (cf. :rst:dir:`tabularcolumns`).  If the
+        table column specification (using :rst:dir:`tabularcolumns`).  If the
         document is configured to use the ``'colorrows'`` table style, a table
         wishing to use column colours should receive the ``nocolorrows``
         class.
 
       - Multi-row merged cells, whether single column or multi-column
-        currently suppress all kinds of cell colouring.
+        currently ignore any column, row, or cell colour.  Only single-row
+        merged cells respond to colour, and only to the sole row colour.
 
       - It is possible for a simple cell to set a custom colour via the
-        :rst:dir:`raw` directive and the ``\cellcolor`` LaTeX command located
-        at the very start of the cell contents.  But this is currently
-        without effect for any kind of merged cell.
+        :dudir:`raw` directive and the ``\cellcolor`` LaTeX command located
+        at the very start of the cell contents.  This currently will remain
+        effectless if used in a merged cell, whatever its kind.
 
    .. versionadded:: 5.2.0
 
@@ -2305,7 +2307,8 @@ These options influence LaTeX output.
       white gap between the bottom row and the bottom rule, and between the
       first body row and the (mid or top) rule above it.  It is possible to
       extend the background colouring to touch the rules, via some extra LaTeX
-      coding.  This may be added to Sphinx in case of feature request.
+      coding.  This may be added to Sphinx in case of feature request, but
+      this whitespace is considered currently a quality rather than a defect.
 
 .. confval:: latex_elements