Deep XML modification..

[nobody]

Whats the best way to modify deep branches of XML?  The tree is eight levels
deep, so I have a forrest of cloneNode and replaceChild, to propogate
changes from the leaves back to the root Document.  There has got to be a
better way?  I also want to avoid pre-sorting the data into a list, and keep
it entirely XML if possible.

I'm using DOM but SAX will do just as well, I don't care either way.  The
Python XML HOWTO was pretty thin, and DOM was easier to figure out :)