I agree with it in some situations... some people are genetically predestined to be fat unless they have a super strict diet and exercise daily. These people grew up as obese children and obese young adults. By the time they realize they need to do something they are 350-400lbs. Try exercising at a gym when you are 400lbs. We all say "if I was that fat I would stop eating." People who have this problem often times have a psychological disorder or reliance on the food. Its like telling all smokers to quit cold turkey or alcoholics to put the bottle down. Imagine a surgery that would force you to only smoke one cig a week or only allow you to drink 3 beers a week. (being 400lbs is much worse then either of those habits) Stomach stapling sounds terrible and unnatural but for some its their only option.
Its like lifting weights. If you lift weights for a while and don't see results then you are likely to give up. Conversly if you see big results you would be more apt to push yourself harder and stengthen your workout. The stapling gives near immediate results which is usually accompanied by increased confidence and self esteem.
