yes, but decades of experience in what though?
I think you will find that Medical research and Mainstream medicine know very little if anything about the fast and the fasting process, otherwise they would be out of business for the most part.
I very rarely read any information within the medical field as this is mostly irrelevant with achieving good and robust health, but it is the experience of Natural Hygiene and Orthomolecular Medicine in particular that the greatest leaps are made in achieving the above.
It is mostly irrelevant as to the starting point of a persons weight when undertaking a fast in the recovery of health, as even the most underweight person has enough food reserves to see them through a period of prolonged abstinence (although this should of course be a fast that is supervised by qualified personnel). It is well-established that thinner people tolerate fasting better than someone who is overweight.
"Sylvester Graham denied that the fat man lives longer on prolonged abstinence from food than does a thin one. He says, "If the it be designed for the nourishment of the body during protracted fasts, etc., then if a very fat man, in the enjoyment of what is ordinarily considered good health, and a lean man in good health, be shut up together, and condemned to die of starvation, the fat man ought to diminish in weight much more slowly, and to live considerably longer than the lean man; but directly the contrary to this is true. The lean man will lose in weight much more slowly, and live several days longer than the fat man, in spite of all the nourishment which the latter may derive from his adipose deposits."--Science of Human Life, pp. 193-194. http://www.soilandhealth.org/02/0201hyglibcat/020127shelton.III/020127.ch6.htm
Your opinions may be based on what you refer to as "commonsense", but this does not seem to tally with the
decades of experience from Natural Hygienists who have supervised thousands upon thousands of fasts in most conditions of health and disease, with unparalleled success, in persons of differing starting weights, including the underweight, dating from the mid 1800's.
Yes I would agree with you, it is indeed true to say that the fast is unnecessary (except as an an annual cleansing measure) if anyone adopts lifestyle habits that conform to our physiological and biological needs.