RE: JTCS - Viet Nam
Hawk, it is not 10 clicks an hour, but 11.125 clicks due to double time. As the default average for all grunts. That is a 3 hr 45 minute marathon. Battle gear, combat boots.
The larger the scenario the more things become unrealistic (per 6, or 10, minute turns), agreed. All action, no pause, God view to all units on map, no unit disobeying or misunderstaning orders. But that's another thing isn't it.
I've explained this to gamers by saying there's the game (base) scale as how units are designed.
Then there's the scenario duration, the latter depending on playtesting, with number of turns required matching expected results, and that is that.