I have read a great deal of Chinese history. I have also read many of the philosophy classics; Confucius Analects, the Tao Te Ching, the I Ching, and the Chuang Tsu. Chinese philosophy does not set forth ideas as directly as Western philosophy. You can read three sentences and search for the meaning for fifteen minutes. The writing conveys ideas in what is to me an abstruse fashion. I briefly studied the Chinese language and it conveys a lot of ideas in a short space.
After the thinking I do get an idea. It is amazing what is conveyed in a few words. There is no attempt to set forth an ordered set of ideas. What I understand are thoughts that form a point of view. That is what I mean by inscrutable.
Mencius is not nearly as minimalist as the Analects. He tells short tales with a moral. To that extent he is easier to understand. The same ideas appear with different emphasis in tales. The writing does not present a clear direct system of ideas, such as Aristotle. My interpretation may be much different than yours.
I enjoyed Mencius. I felt it was worth while and gave me insight into Chinese thought. It must be remembered that he is second only to Confucius in Confucian thought.
What worked for me was to read slowly and take notes. I had to invest a great deal of time in reading what is a short book. I still feel I need to read some type of treatise to get a better understanding of the philosophy of Mencius. Reading Mencius first gives the basis to build a greater understanding of Chinese philosophy and the Chinese point of view.

What can I say? This book is probably the closest Chinese book involving the art of parallel-argumentation that a person will ever get out of a Chinese book.

I love this book. Plus, Lau really adds desert by his five highly detailed appendixes. Way to go Lau!