bzr checkout --lightweight ~/bzr/trunk /tmp/bzr-checkout does work for me, so there must be something more subtle about it - perhaps it's specifically to do with a lightweight checkout of a remote branch (which we wouldn't normally recommend).
bzr checkout --lightweight ~/bzr/trunk /tmp/bzr-checkout does work for me, so there must be something more subtle about it - perhaps it's specifically to do with a lightweight checkout of a remote branch (which we wouldn't normally recommend).