Nope. What I'm saying is that once you do that, you run a much higher risk of alienating your employer by saying or doing controversial things. They certainly can't control what you do or say, but they may well opt not to employ you because of the choices you make. There's a distinction there, and it matters.

(Also, in this case, I do believe that she used her twitter feed for 'official'/work-related duties, so that does genuinely blur the line between personal and professional)