I don't think that really describes it either without knowing that a relation has a local pointer. I'm being pedantic, so unless someone else has a better suggestion you should probably just leave it as is. 

The django docs explain (briefly) about the database representation of foreign keys, but never really mention the local source field (https://docs.djangoproject.com/en/1.6/ref/models/fields/#database-representation). Perhaps if it was mentioned there and linked to from the release notes (order_by now respects a foreign keys ('local source field')_ )? But that's probably going beyond what this patch is attempting anyway.