The one-star rating here is unfair - the reviewer makes a valid point, but I think they may be taking the book out of context a bit.
To get the most out of the stuff in here that discusses how specifically to tackle problems, be they numerical, geometric, or something else, you need to use this as part of a university course. I am not sure if the other reviewer did so - they did mention its use as a lab manual. If they did use this as part of a class, their problem with the examples in the end of the book is their own. They should have asked the instructor for help with the problems. This is not like a basic math or physics textbook that has tons of examples with answers for you to work through.
It is instead a comprehensive manual of basic methods used in structural geology. With just this book (and a knowledge of the subject, perhaps with a regular structural geology textbook as reference) you can tackle almost any structural geology problem you can think of. It doesn't exist to handhold you through everything. It's all there, but if you don't understand something right away you need to put some effort in to figuring it out.
In structural geology-related courses I took, with certain complicated problems I had to spend hours and hours more or less simply staring at it. I would look at the problem, read through the techniques described in this book, look at the problem again, and spend a long time putting everything together in my head until it makes sense. I'm sure there are other approaches (depending on if you're good at visualizing things in three dimensions or not) but that is what worked for me. This method was also advocated (in so many words) by Gautam Mitra himself in my discussions with him (he taught the structure courses I took at the University of Rochester.)
The techniques in the book work, but for many people it is going to take a lot more effort than problem-solving techniques in many other sciences that take less time to visualize and understand.