I'm curious to read the book. I've practiced breathing techniques from yogic and meditative traditions for maybe 15 years now. Even just a minute of deeper, slower breathing has a calming effect on my mind and body, for the most part.
The breathing practices/exercises are, for the most part, useful and interesting. I have to let go of a lot of the metaphysics in these traditions though, there is a certain amount of "woo" to wade through.
I've been a software engineer for 15 years, have meditated with varying degrees of consistency for 10 years, and have taught meditation to peers, friends and the public for the last 3 years.
The conclusions reached in this article about the temporary nature of all states and experiences, as well as connecting with the wisdom of the body, resonate strongly with me. I'd add that the ability I have developed to monitor and redirect my thoughts, as well as enhanced concentration, are other direct benefits.
I believe you can see some benefits from meditation without embracing the full retreat experience. But a retreat is definitely a step-up and solidifies a lot of the lessons. I've done 8-day insight retreats which are a little less austere than Vipassana but seem to bring about similar states and changes.