Folks, we train like this for a reason. And there has been distinct interest in modern diesels and the threat of modern diesels has been openly discussed. If this war game opens some eyes in leadership that's a good thing. Hopefully, brass doesn't share the prevailing attitude on this thread of "can't happen."
In many cases, war games tend to reinforce existing paradigms for the winners, and -- in ponderous bureaucracies -- result in little more than career damage for a few of the losers. On few levels is there significant, "Whoa, let's FIX that!" if it involves significant investment, counters long-embraced attitudes, or challenges the pet entrenched branches for resources.
IIRC, war games held by the French in the mid 1930s demonstrated that a force attacking from the east could simply move through the Ardennes and bypass the line. The reports were quashed, the idea pooh-poohed as unrealistic, and the officers responsible for embarassing the high command got reassigned to dead-end positions.