The 2007 NICE guidelines nice.org.uk/guidance/cg53 suggest;
Cognitive behavioural therapy and/or graded exercise therapy should be offered to people with mild or moderate CFS/ME and provided to those who choose these approaches, because currently these are the interventions for which there is the clearest research evidence of benefit.
Research suggests that for some graded exercise will do more harm than good
which if the doctors remember the Hippocratic Oath
"I will prescribe regimens for the good of my patients according to my ability and my judgment and never do harm to anyone"