Black Friday is not another bad hair day in Wall Street. It's the term used by American retailers to describe the day after the Thanksgiving Holiday, seen as the semi-official start of Christmas shopping season.
Planning is really the hallmark of any large military formation, and it's typically a weakness in new formations and new armies.
I really love helping students and helping them empathize with people who lived a really long time ago. That's one of the highlights of working in fiction.