I highly disagree and I will tell you why:
BJJ is a very young sport. We are talking maybe 15 years of solid high level world tournaments. In addition, most practitioners come from 2 cultures.
Now, look at wrestling which has had world level tournaments since the ancient Olympics, and every country on earth is competing.
Wrestling, in contrast to what Mr Kesting is stating, has practioners at the elite level with wildly different successful techniques. It has so much variety and many things work that do not seem like they should work or that coaches say are junk moves. Why is this?
The reason is simple. Wrestlers have always known that the techniques that work the best are the ones that suit your body type and that you drill more than all others. There are techniques that are lower percentage, but that is because a lower percentage of athletes put in thousands of reps on those techniques. They dont start with those techniques in gradeschool and hammer them out til adulthood. Peewee coaches will sometimes think along the same lines as Mr Kesting. "Because singles and doubles are the highest percentage of takedowns at NCAA's, they are the best and that is what we will focus on. No head and arms, no firemans, no throws because those are low percentage" In theory, that works, until you go to places like Russia or Mongolia where firemans carrys and throws are drilled from the start. There is more than one way to skin a cat.
BJJ is exactly the same. There are techniques that are less successful because almost no one perfects them and makes them a staple of their technique. Lets take Marcello for example. I would bet money that he has drilled and pulled off 10,000 guillotines in his life. In competition, he has proven that that technique, for him, can beat the best. Now, if Marcello had 10,000 Americanas from side, he could pull that off in competition just like a guillotine. We would have the Marcelacana. Even the rubber guard, which many bash as ineffective, was shown to be effective against one of the greatest of all time when Bravo took on Royler. Was it because the technique was good or bad? No, it was because Eddie had thousands and thousands of hours in that position and made it work for him.