The Minnesota document referenced is dealing primarily with topic of energy conservation and makes recommendations for reducing energy demand. These recommendations may or may not be agreement with current best practice re sizing of water distribution systems nor is there any certainty that such recommendations will be in agreement with code requirements such as those promulgated by State of Massachesetts.
If you are truly interested in sizing hot water demands, I would suggest that you obtain a copies of the American Society of Heating, Refrigeration, and Air Condition Engineers Applications Handbook, the International Plumbing Code (IPC), the Uniform Plumbing Code (UPC) and the American Society of Plumbing Engineers handbooks that deal with this topic. You will find that each of these use probability theory to account for the various unknowns, which has been briefly mentioned in this forum. Depending upon your background, you may find it beneficial receive some formal instruction on the topic as well.
I'll be more than happy to have a discussion with you, but continuing to berate longstanding members while contributing little more than a series of incongruous statements, nonprofessional opinions, and weblinks does little to enhance your credibility on this or any other forum you participate in.