I think it's important to have closure in any relationship that ends - from a romantic relationship to a friendship. You should always have a sense of clarity at the end and know why it began and why it ended. You need that in your life to move cleanly into your next phase.
The real beauty of it - key to my life was playing key chords on a banjo. For somebody else it may be a golf club that mom and dad put in their hands or a baseball or ballet lessons. Real gift to give to me and put it in writing.