Great point. Each pair will usually find the right balance of pairing time and breaks, but using the Pomodoro technique (http://www.pomodorotechnique.com/) is probably a good place to start.

I don't think the uncomfortable aspects of pairing are unique to pairing as much as they are compressed in a much shorter space. No snarky emails during code reviews or awkward hallway conversations. It's all right there, in real time.

I _really_ love hacking on code alone, but every pairing session I've had has been memorable and the code has most certainly been superior to what I would have done solo.