MVC and multiple XML files

Hi all
Im trying to work out how to load separate XML files for each section of the site, which is built with MVC. I didn’t write the code, so this is already tough - the site is heavy and I’ve been asked to lighten the sites load time by splitting up the XML loads, by chopping up the single XML file into several individual XML files.
My problem is that I cant work out the best way to achieve this. At present the Document class loads in the XML. This then creates an instance of the Model class with the XML data.
My problem is that I can’t work out the best way to tell the Model class to load a different XML file each time the Navigation View class is clicked, as there is no connection back from the Model class to the Document Class.
dai2
:p: