git fetch --reference?

["Michael K. Edwards" <medwards.linux@gmail.com>]

When setting up a working area for kernel integration for a new
embedded target, I generally do a "git clone --reference" so that the
new area has its own repository (and its own branch structure) but
most of the blobs come from a local reference copy.  But now that I'm
integrating bits from several non-trivially divergent trees (mtd-2.6,
netdev-2.6, linux-2.6.16.y, etc.), it would be nice to avoid
re-downloading blobs for these additional remote branches, which are
also available in the local reference copy.  Is it feasible to
implement "git fetch --reference" for this purpose?  Or is there a
better way to manage this sort of integration effort?

Cheers,