<p>ah yes the written work. I think that's a really good aspect about the oxbridge application. Perhaps American universities should think of including that too.
A sample of your written work (especially something written in class with limited time) is probably the best indicator of your potential. This criterion also allows you to submit your best performance (as opposed to standardized tests, which some people just aren't able to do well on).
That said, I have no idea how much oxbridge value each separate part of your application.</p>