I have always read the same.....but I have always wondered how much of the "consistent flavour batch to batch" is science (not sure what the science would be and would definitely be interested) and how much is marketing. Seems to me that mash pH needs to be lowered for enzymes and yeast and distilleries happen to have a free source of acid (backset/dunder) to use and make things more cost effective than purchasing acids. That said, rum won't taste like rum without some sort of bacteria (i.e. dunder pit) in my experience (tried to make rum, tastes like molasses distillate and none of the rum-like headsy flavours...suppose I could have distilled it differently with wider cuts but rum was just an experiment).