I think it's important to explain that major depression is not even peripherally related to "sadness." Depression is the absence of emotion. I never cried during my darkest periods of depression. Crying would have been A HOLIDAY. It would have been F***ING CHRISTMAS. A fight or a feeling of anger would have been AN EASTER EGG HUNT AT DISNEYLAND.
There are fascinating lessons to be drawn from the use of Twitter by comedians. Twitter, somewhat unexpectedly has found itself to be an oasis of comedy. The making of comedians used to be shows like Mock the Week and Have I Got News for You. A blistering performance there and the Hammersmith Apollo would soon be beckoning. Frankie Boyle commented recently that now no comedian need to wait for their day in the sun to blurt funny topical lines on TV panels shows, they can now ad lib in the moment on Twitter.