freeing up storage space that was accidentally hogged by a file in repo

[Rahul Nabar]

One of my automated scripts accidentally added a somewhat larger and
also quick changing file to the repo. Is there a way to permanently
remove it from the archive to free up all its storage? "bzr remove"
won't really affect the historical storage it has occupied, right?

This time it is not so critical because I detected it fairly quickly
and the file was not that large. BUt I am just wondering what happens
if I accidentally end up adding say a 100 GB swap file to my repos. Is
the act irreversible or is there a way out?

A related question: Can I perform forensics to know how much storage
(at least approximately) this file is occupying under the bazaar repo?
This can't be solely a function of file size since it ought to also
depend upon the frequency and magnitude of changes integrated over its
lifetime?

-- 
Rahul