Some recent discussions on Boardgame Geek got me to thinking again about the problem of Hindsight Bias in historical wargames. Simply stated, a wargamer playing a Gettysburg game of any sort, no matter how realistic, enjoys a major advantage over the historical Lee -- he knows how it turned out. Or perhaps even more importantly, the gamer knows the potential range of possible outcomes.
I don't think there's a way out of this dilemma directly. You can only introduce so many changes into a game about Gettysburg before you're not playing a Gettysburg game any more.
But this is why I think there's some value in playing alternative history or what-if scenarios or wargames on occasion, because it can give the player a little taste of the situation facing the real commanders. For them the battle was the first 'playtest' and they had only a vague idea of the rules, let alone victory conditions or OB.
Mixing in a few alt history games can help keep in check our tendency to judge the actual participants a bit too harshly, much of the time. I know I wouldn't want to be judged on my first play most of the time.