I kinda want to chime in here with my own personal experience. First, let me say I am very well aware this is not remotely comparable to OCD. And I'm not saying this is the case for Hannelore; I agree with people saying this is a breakthrough, not a cure. But...
For most of my life, I had a serious nail-biting problem. Like, constantly, they were always bitten down to the quick, my fingers hurt all the time. Awful. Tried for years to quit. Then about...seven years ago?... I told myself one day, you are in control of your body. It does not control you. You are stronger than this. And...it worked. I've had a few setbacks, and I still bite the skin around my nails sometimes, but for the most part I haven't bitten my nails since. I don't know how it worked, I know it wouldn't work for most people, and people aren't weak or "not trying hard enough" because they can't just will themselves better. And like I said, nail biting is not OCD. But I can believe that, once in a while, someone CAN muscle their way through their issues through sheer will power alone.