Hi, Roos_Girl . . . I find this amusing. Some of the worst teeth in the world we've seen in the office have been in people from Great Britain. However, this Emeritus Professor is right that if someone is flossing wrong, they can do more damage than no flossing at all. If one were to floss downward from the top of the teeth toward the gums, instead of upward, they will be packing food particles and scraped off plaque where it should not be, into the gum line where it can rot, creating the problem flossing is intended to prevent in the first place. The headline, which was probably not written by the Professor, was designed to grab readers and clicks. Unfortunately, most people won't get much farther into the article
than the head line.
Our office's protocol is still the same. Brush with baking soda and every week rinse and swish around the teeth with Dakin's Solution (a 1 to 20 Clorox Germicidal to water solution) to kill whatever bacteria survive the baking soda. Use a power type irrigator to get the solution down into the gum line. Floss. . . properly. Done.