read hooks

Subversion has a number of hooks that are called when data is being
modified, but I'm curious if there is any way to create a hook that
is called when data is simply being read.

My specific use case is that of student privacy here at USC; US law
states that a student can request the university not release any of
their personal data. So for those students, I'd need to be able to
mask the svn "author" attribute in some way. My first inclination
was to write hook that intercepts a read request and masks the
<D:creator-displayname /> for those students who have requested this
confidentiality. Is that type of hooking available, or would I need
to dig into the subversion source? Or is there some other way to
achieve this perhaps that I'm not thinking of?

Thanks,
Will