Transform Problem Too Much IO

Hello,
I have a problem that I could use some input into. I have a xml file which describes a html document (textareas, selects, form elements).

I have always included a stylesheet in the xml document which points to a xsl file. Management now wants us to transform in the server using xalan. And that is their choice and I can do that. 

The problem is, I need to insert a few nodes into the xml before transforming. The nodes I am inserting are describes in the xsl, but in order for me to insert a string of nodes, I have to open the xml file (file io), substring the new insert in, then write the file back out to disk(more file io).

I have the prototype working, but we cannot go live, due to the IO problem. How can I insert a couple of nodes into a xml file, without beating up my system? I also looked at xalan where I am transforming the doc, and it looks like it only likes file ans filestreams.

Could someone shed some light on this?

Thanks,

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