For all we know the ketones are just the 'pedalling frequency' or the oval chainrings 'busting my ass off 6 hours a day' or any other marginal gain that's really a distraction from 'god this juice is good'Outskying Ineos. But lets wait for the Tour.
By the way, from what I understand Ketones are produced by the liver in a fasting state (or under carbohydrate restriction) but can apperently also be supplemented. The evidence of performance effects seems to be limited. So why is there such a big buzz around it? Even more so if it is not prohibited and just another supplement. Coffein or Magnesium probably have more studies backing performance effects for example (which does not necessary mean Ketones are useless or may not indeed have greater effects but it does not seem to be a gamechanger to me).