The idea of using a physical practice to improve ones ability to make and keep commitments is, as far as I know, a Chinese idea. It's called gongfu (kungfu): meritorious action.
Dr. Laura is Jewish and conservative. I don't really know how yoga was practiced historically in India, but I've never heard of a traditional context in which it was used this way. I don't want to say it's just a Chinese idea because I think the idea is common to various North Asian cultures, but as far as I know Judaism, Christianity, Hinduism, and Islam do not contain this idea. Protestantism has the idea that "work will fix you." And Catholicism has the idea that something slow and painful (like yoga) can bring you back to "God's virtuous path." But both of those are quite different from the idea that a physical practice will improve your ability to make and keep commitments.
In the traditional Chinese version weak commitments, or the habit of repeating an action you know isn't appropreate, is often considered to be the negitive influence of lingering ancestoral "ghosts." Dr. Laura even hinted at an ancestoral cause by saying that in the caller's family a lot of crazy stuff seemed normal and yet she was going to have to change anyway. Yoga is being used as a form of gongfu, and the idea of gongfu is spreading fast, even on AM radio!