In the second diagram in "Stop bug spreading" at http://www.plasticscm.com/infocenter/quick-start/intro-task-driven-development.aspx, it says "This check-in introduces a bug, but only "john" will get affected by it until he merges". It was "pat" that made the change, so presumably "john" should read "pat". Either that, or I'm completely misunderstanding the concept.