I agree that Nestor's book should not be considered canonical but this sentiment goes way too far in the opposite direction. I have seen enormous improvements i

I agree that Nestor's book should not be considered canonical but this sentiment goes way too far in the opposite direction. I have seen enormous improvements in my overall wellbeing since I started focusing on my breathing about four years ago. Prior to that I have both been a nationally ranked competitive cyclist and avid pickup basketball player so, in other words, quite fit. Of course my personal experience is inherently unscientific but it is also true. There are many, many positive effects that I have experienced that are directly related to my focus on the breath, but of course there have been other factors in my life too. I agree that just focusing on the breath alone cannot fix every problem (and wish some of the more zealous evangelists would dial back some of their claims) but I am quite certain that just exercising is not sufficient for many people. Conscious focus on the breath is important.