Ms Dafoe Whitehead and Mr Popenoe put it like this: “Working as a couple, individuals can develop those skills in which they excel, leaving others to their partner.”

Ideally, in Stage Two couples learn to deepen their communication skills. They work to understand and express their wants, needs, and feelings.

Each couple was then videotaped while having conversations, and researchers graded them on their communication skills, noting who had distressing or hostile styles of communicating.