I wonder if the "default to humility" heuristic probably does more harm than good on net, because the people who heed it probably shouldn't, and the ones who should won't.
Default to humility. Do not assume you're so smart that you can skim the text and understand it correctly. Read every word, don't assume that the author is so predictable that you can guess correctly.
Why, does not sound too arrogant to me.