Ideas are developed using examples, many of which are case studies in which data from experiments are brought to bear on scientific questions. However, statistics is not merely a set of methods for analyzing data. It is also a way for integrating data into the scientific process. The process of learning requires calculation. This in turn leads to a secondary emphasis on methodology.
Calculations involved in developing and motivating general settings can be tedious.
I have endeavored to keep difficulties with this aspect of the learning process to a minimum. Not all data sets are fodder for statistical methods. There must be a well-defined question being addressed. In my view, applying statistical ideas requires familiarity with the substantive scientific issues and should not deal merely with numbers. So it is inevitable that readers will learn some science as well as some statistics.