This book was well-written in terms of prose. There are a few places where mistakes were made that could have been caught with a careful copy-edit, but it is few enough to not distract entirely from the content.
The story chosen is excellent. Doyle's writing makes for a good selection in terms of a story to deconstruct.
The biggest issue I have with this is that it feels like a standard treatise on the 3 act story structure that uses A Scandal in Bohemia as an example. Reading the description of the book, I thought that it would be teaching me a framework to examine any story in this style, rather than reading how the author deconstructed 1 specific story.
My advice to the buyer is this: Read the seed story (in this case A Scandal in Bohemia) BEFORE you purchase this book. If the story seems to be one that you are wanting to tell and you need help picking out the elements through the lens of the 3 act structure, get this book. If you are looking at examining how to deconstruct stories based on that 3 act structure without any preference for the source material, an internet search can find enough material on 3 act deconstruction to get you what you need.