We really need a way to do migrations.  Don't we have a way, just creating a new manage.py command that does whatever you want?  They're kind of hard to test, but if not for that it seems really wrong to do things this way.   Like, should you add a comment saying "remove this code once all of the domains in existence before 2/28/13 have been visited at least once"? (or is there some page that loads all the domains?)