Writing with Another Writer

I was about to title this "workshopping vs. writing," but I felt the dichotomy rang false. These aren't two activities pitted against one another. They are both important--even to the seasoned writer. Established writers maintain long-distance correspondence with trusted readers for years. Perhaps what I actually want to discuss here is this: the benefit of writers getting together simply to be writing in the same space.

I have a short attention span, well, short-ish. I can be intensely focused, but I am easily distracted. However, when I write in the presence of someone else who is writing, I can focus for the better part of an hour (if not two or more). I have a few fond memories of this. The first, in high school: my friend and I used to sequester ourselves in his bedroom for hours to listen to music and write plays, poems, and whatever else interested us. In college (and I may be mis-remembering this a bit) I wrote once or twice with a girlfriend in the living room of her ground-floor apartment. In grad school I spent a whole evening in the sitting room of my fancy, turn-of-the-century apartment (a story for some other post) scribbling away with my roommate and a classmate. And, during the past year, on several afternoons, my workshopping buddies and I met at the Bean Exchange in Philly--not to discuss work--just to churn it out. So, please forgive the nostalgia. As I arrange a collaborative writing session with some writers I know, I have been thinking a lot about "writing with others."

Have you--oh my often ignored, but dedicated readers--written in the presence of others who are writing? Would you share an anecdote or two? Or, have you worked on a piece, collaboratively--in the same space--one writer's hands on the keyboard/paper, the other writer speaking? I don't think I'm romanticizing the value of this practice. While this practice may be more helpful for extroverted writers like myself, there must be benefits to any writer. No?