is this accurate? http://www.lowcarbluxury.com/yogurt.html

"These bacteria use up almost all the milk sugar called "lactose" and convert it into lactic acid. It is this lactic acid which curds the milk and gives the taste to the product. Since these bacteria have "eaten" most of the milk sugar by the time you buy it (or make it yourself.) At the time you eat it, how can there be much carbohydrate left? It is the lactic acid which is counted as carbohydrate. Therefore, you can eat up to a half cup of plain yogurt, buttermilk, or kefir and only count 2 grams of carbohydrates "