catalogs and xslt 2

Is there any reason why the Apache catalog resolver shouldn't work with
Saxon 8.4, xslt 2.0? I can't think of any...

What changes should I make to the latest docbook html or xhtml
stylesheets to enable xslt usage? I have no problem going through each
stylesheet and modifying (I'm doing that already). 
  Where are the extensions called up please? I guess that's an area
a) I know nothing of.
b) I'm unsure what needs omitting/changing.


TIA, DaveP

ps. My end game is a set of docbook stylesheets which
are not configurable, and which output XML according
to www.daisy.org... or its near future relation, the NISO 2005 standard.

One lesson I've learned, the 'simplification' of html output can be
done to quite an extent in the titlepage.templates.xsl file!

Another is that NDW|BS is|are a bit on the clever side! There's some
pretty smart code in there !