Yes come on, does anyone still think they are useful and simply not a complete waste of developer time?
For some things like libraries and such, there are absolutely needed, but unit testing everything and especially TDD are stupid.
To be frank, they mostly sound like some Java EE-like monstrosity that for some bizarro reason caught on with the hip crowd too. I'd put them out there with FactoryOfFactory and XML documentation...
It's definitely some solution for testing. But when you're writing a webservice, you should think twice before assuming that anything a "UNIX programming god" says is a good advice for you.