Speaking of common sense: One of the reasons that colon cleansing is so popular is that folks seem to have a skepticism of their own diets and eating habits. So they resort to cleansings so extreme that you need to stay within 10 feet or your toilet or wear adult diapers through the process! If you followed the type of diet, high in fruits and vegetables that physicians and nutritionists have been recommending for years, you will find a pretty normal digestive system and colon and the aforementioned 2-3 BMs/day! I've even seen cleansing diets that totally emphasize a diet made up exclusively of natural (aka "raw")fruits and vegetables to get the cleansing results. Ask yourself this: "If you were 100% confident in the health aspect of your diet, would you ever be concerned about the health of your colon?
I can surely understand some of the skepticism of traditional medicine, but you've got to be equally skeptical of alternative medicines' suggestion of something as crazy as lemon and flaxseed oil cleanse too.