What about from people who are medically qualified? Saying the exact same thing? Publishing research saying the exact same thing? Clinically advising the exact same thing? With the same intent and purpose? Officially? With consequences, for insurance and disability? Valid expert opinion in a court of law?
What about then? Because the "carefully managed" bit is complete red herring. There is no such thing, it makes absolutely no difference and may as well say that it's "supervised by Santa Claus". Comments like this actually show how significant the problem is, because they give weight to the same lie using different words. This is exactly what the PACE-type ideologues have been saying for years, with the same intent and purpose. They keep using the No true Scotsman fallacy and almost no one cares, it's an accepted fallacy here.
What's worse is that it's written explicitly in those terms. This "asking patients to exercise just on the idea that they've changed their mindset about it" is exactly the premise of PACE, and PACE is the foundation of the entire treatment model. The problem isn't just LP, it's the profession that has lost its way. Even the worrying about symptoms is core to the official CBT+GET model, and to the generic psychosomatic rehabilitation model.
Actually there is a way to read this that basically means that doing LP is problematic, but doing CBT+GET is fine, even though they're basically the same thing. Which is basically one expert criticizing pseudoscience on some basis, who then promotes the same pseudoscience in the same sentence, even though it features the same problems.