Moreover, people are rarely told they can't work together anymore because they're friends. But the potential fallout from a looming romantic breakup can be enou

Moreover, people are rarely told they can't work together anymore because they're friends. But the potential fallout from a looming romantic breakup can be enough that HR may force an employee to switch departments (as happened in the article at hand). Beyond that, favoritism from romance tends to be much stronger and far less rational than favoritism from friendship. Indeed, work friendships are even often formed on the basis of a mutual recognition of competence. Romantic friendships are usually based on factors utterly unrelated to performance at work.