What are "Net Carbs" and should Sugar Alcohols be included?

Net Carbs is a simple idea (carbs less fiber), used by all Ketogenic Diets (except “Keto Clarity”). However, while the Atkins Diet also subtracts sugar alcohols, most Ketogenic Diets don’t. I try to explain this simply while giving the science to back it up. http://fellrnr.com/wiki/Net_Carbohydrates