true, lol. Not suprising. Jack Wattley who really is the father of the American Discus hobby has often given conflicting advice to readers. One month he will hammer a reader for not doing daily water changes, than the next month he will say that 2 water changes weekly is more than enough leaving one to ask, "what is the right answer."
Really the right answer if whatever works for a given person, as I am sure Discus are kept in a variety of conditions that Jack Wattley, myself, and likely BrianNY an advisor here would not advocate, but they may thrive in that condition.