Enhancement: displaced .svn

Hello,

I was thinking for some time about new feature, displaced .svn. As I
don't know svn internals, I'm looking at it just as user. Also it might
been asked and answered before, but I haven't found it.

Description:
Normally in every directory of working copy you have '.svn' directory
containing some metadata required for svn. I am thinking about way
getting those metadata out of actual working copy. My idea from the user
point of view is to split working copy directory and metadata directory
into two independent paths.

You would have environment variable like SVN_METADATA defining the head.

When the variable would not be set, everything would work as normally.

/work/project/
/work/project/.svn/
/work/project/README
/work/project/src/
/work/project/src/.svn/
/work/project/src/a.cpp

If you would set SVN_METADATA to /work/project.meta, it would work as:

working copy:
/work/project/
/work/project/README
/work/project/src/
/work/project/src/a.cpp

metadata:
/work/project.meta/
/work/project.meta/.svn/
/work/project.meta/src/
/work/project.meta/src/.svn/

I hope you have the idea.

Why:
a) Your working copy would not be clobbered, you could just tar.gz it
  and ship
b) Imagine having network drive used for collaboration. You could have
  the drive under svn control with the metadata stored locally, which
  would not bother other people using that drive. The drive even does
  not 'need to know' that it's versioned. And you would not vaste
  network drive space for your obsession by svn :)
c) You could use b) as poor man's incremental backup, without affecting
  the data

My questions:
Is it sane from the svn internals view ?
Do I have any chance to get it implemented ? :)
If I start to create patch for this, is there chance to get it to the
  trunk ? Under what conditions ?

Thank you

--
	Vladimir