Graded activity is an important component in CBT to reduce severe fatigue: cancer survivors (Knoop et al., 2019)

I doubt Gary’s post cancer fatigue would have ever got to Knoop or been considered for psychotherapy. Major thoracic surgery leaves people in catabolic state for months - as he says a purely physiological reaction to tissue trauma. The people Knoop treats appear to be in a different category.

But who knows what category that really is?