Red, I'm speaking about the actual boiled Munich profile which still has significant alkalinity left in it. For that water, those Munich brewers would have to include that acid source. For someone starting with a low alkalinity water, you may not want to go to the trouble of creating the boiled Munich profile with all its alkalinity and then reverse course and add acid. In this latter case, you probably wouldn't add any more alkalinity than necessary for the mash condition.
But to be as authentic as possible, boosting the alkalinity to the boiled Munich level and then adding the lactic source may be the way to go. Those of you with fairly alkaline water may consider this an opportunity! I remember my Tallahassee water was well suited to making Hefe's and Dunkel's since I used Lactic acid exclusively.
Unfortunately, the recommendations that Kai makes regarding the water for the Dunkel are dated. He may want to revise that water recipe.