My assumption when reading that message was that it would appear to update the storage class, but actually create a copy of objects with a different storage class and delete the old objects. It doesn't make sense that it would just duplicate my objects, and I still can't really imagine anyone wanting that. Why would a box called "Edit storage class" create a copy and then not destroy it? Why not make a dialog box that just...edited the storage class?
So maybe I had a previous version of all my files sitting in regular S3, with the current version sitting in Deep Glacier, and I may have just happened to delete previous versions of objects when I created the lifecycle rule.
To answer your question -- I don't think we're following any of the pillars of well architected frameworks. I'm a filmmaker who knows Javascript and PHP and not system architecture, and I was looking for a cheap way to not lose our movie to the ravages of time. I'm definitely not the only one.