Preload PHP generated XML

I know it is possible to preload XML, but what about XML generated by PHP. For example,
I am creating an XML file by making calls to a database and outputting it as XML:

http://drewestate.com/new/2008/loadblog.php (right-click & view source to see it)

So, is it possible to preload that xml?

well the only issue would be ensuring the xml is fully created before the "get xml " code is called

Thats what I am saying…I am thinking its going to preload the php page which then it wouldnt be accurate.