Barely usable is dramatic, but the multiple interfaces to do seemingly the same thing is annoying and I agree makes usability a challenge. What differentiates when a setting is in the old Control Panel versus the new one? What's the difference between Edge and Internet Explorer, and why is my browser sometimes a traditional window and sometimes a full screen, touch focused app (this is a gaming PC hooked to a TV, so no touching)? I'm often accused of being an Apple fanboy, and while I try to stay agnostic, I think some of the things Windows has done with 10 are pretty confusing, though markedly better than whatever they tried to do with 8.