Tracing is a very broad term.
The article is actually interesting, the person who wrote it seems to be using tracing, in fact to better himself, not just to end up with a perfect photo-realistic picture, traced from a photo.
I use "tracing" sometimes to get a stance of a reference photo right. I just use thick lines over the body to pinpoint where the feet are, the point of balance and such. I wonder if you can really call it tracing since I don't actually follow any lines of the original photo.
But in the end, I don't like tracing, I'm much happier with myself if I am drawing from a photo for example and manage to get it right all by myself.
If you think tracing can help you, do use it, just don't rely on it, and don't get used to it. Drawing with your own hands is much more powerful.
Also, if you trace, do make sure that the photos are taken by you or bought. It's really sad when people trace from copyrighted images and act as if they own it, just because they traced it. (usually extreme tracers here, that go with every little detail) Same with reference photos, it's usually better to have your own stock.