"The point, however, is that as a consequence of noticing when our mind has wandered and then replacing our attention on the breath 10,00 or 100,000 times, we are subtly strengthening our awareness of what is happening in our mind and, so, our ability to take control of where we focus our concentration."

So true. But mindfulness doesn't need to be obtained/focused solely by focusing on your breath. I think you can gain a lot of mindfulness strength by training yourself how to (actually) focus on your work: http://focusr.co