No. The hardest part is often the willingness to see things from another's point of view - and to have it be all right for the other to have a different point of view.
In my experience realizing that your partner has different expectations for the actions--Physical Touch, Words of Affirmatio, Quality Time, Thoughtful Gifts, Acts of Service--that affirm your relationship is the hard part. Acting on that realization is straightforward if you are committed to the relationship. It's a good book and one I wish I had read earlier.
It is the hard part. Part of the value of the book is in providing a simple framework for people to understand something a little alien to them. This will increase your chances of understanding. This is not the same as trying put people in a box and limit them, it is more like trying to study what typifies a particular culture and being sensitive to that.
Bottom line, everyone is not you, and to make the most of a relationship you need to understand how they see things, and accommodate.