Method name renaming was licked in Smalltalk, even in things like specs (which predated XML, but served much the same purpose.) So long as everything's an object in the image, you're fine. (Excepting goofy things like constructing message sends at runtime.)

Things like properties files and pickled objects that left the image -- you aren't covered then. But there's little you need those for that you can't do in-image.