50/50 Just Ain't Enough

In my book entitled: The Role of I in Commitment I discuss why the concept of 50/50 really doesn't work in relationships. Ultimately, healthy relationships position themselves in an intricate circle of give and take.  If both individuals truly aim to give 100% (no matter how infeasible it may seem), then on days when one or both parties fall short, there may still be a surplus that enables the relationship to stay in a healthy paradigm.

 What are your thoughts?