Yes, and then you have another optional version of WebDAV, adding to the existing mess, while you don't actually have the benefit of interop that you say would

Yes, and then you have another optional version of WebDAV, adding to the existing mess, while you don't actually have the benefit of interop that you say would be the reason for using WebDAV in the first place. The way I read it, that's basically the point of the article.