Interesting. To me that is simply a physiological relaxation technique, not a meditation practice.
Perhaps the word "focusing" is confusing. In meditation practices such as zazen, breathing is the focus, yes -- but it's a focus of observation, not "thinking about" and definitely not trying to breathe in any particular way. We observe the breath, which will happen anyway -- it's not something that we need to try to do, so it's got special value because we don't need to set our mind (even a small part of it) to the work or effort of breathing. We can just observe it without thinking about it ("Gee, I wonder if I'm breathing right, is this deep enough, maybe I'm getting a cold") and without trying to do it. This contrasts with a number of relaxation techniques in which there is an effort to try and breathe in a certain way. See my earlier comment above.