What to watch out for in wargaming

In not entirely serious mode (or is it?) here's a report on gaming by Major Tom Mouat warning of all the pitfalls inherent in rules, scenarios and gameplay.

Another gamer remarked that the report isn't just about games, and it isn't just about war. We're just going to put it here and ask if you've experienced any of these situations, either on the tabletop or out in the wider world?