David Roundy [off-list ref] writes:
Perhaps a universal --plumbing flag would be handy?
Yes in general but it is unclear what aspect of its behaviour we will
be casting in stone with a generic --plumbing option in this case. I
also think that "checkout" Porcelain is not yet mature enough for us
to do this right now. For example, I am reasonably sure that somebody
motivated enough will teach it to touch submodule trees when switching
to another branch by default, and it is unclear if we should turn off
these expected additions when --plumbing is seen.