The author employs a bold technique I have used for years and does it very well.[1]
Essentially, you bold the essential message for scanners, or those looking for the meat of it quickly.
Done well, it is not too distracting, though I have run into a small number of people who hate it viscerally, and it can guide a busy reader through more quickly and with better comprehension than they may otherwise expect.
Nice work.
[1] - I got started with it in the very early 90's when developing both tech training and documentation. Readers presented the "scanner" pattern consistently, unless they were doing deeper study and had time. In all other cases, they scanned because their info needs were both typically urgent and or associated with a specific task.
I found myself using it in my own notes where I would mark up a text, or write just the bold expressions and fill in later. Going back to my own work, my use of it was significantly improved despite being familiar with it having often authored all of it.
