I began thinking about your question before I saw the blog. There are already some good examples of tweed kilts, the first to come to my mind being the Hodden Grey. However, I think the tweed kilt shown on the blog could be characterized as a fashion tartan- it is after all, plaid, but not tartan. So long as they are made like the one shown, I think they fall pretty well within THCD, but that is only one opinion.