Hi, Martin. I’ve considered those options, but there are reasons that multi-site WP uses the /blog/ slug for the core site — most notably, that it prevents conflicts between core blog post titles and potential secondary site titles. The htaccess solution should not interfere with WP — it should redirect the currently broken URLs to the existing db entries. But it creates all the havoc I described in the post in the process. I may have to go with one of the solutions you suggest here, but neither is really ideal.