These two ends had a lot more to do with why, say, there was a battle at Sharpsburg, MD, than anything General Bullmoose did. I've also tried to validate the conventional wisdom about the battle with some computer analysis. The battlefield maps used are today's configuration, not the historical. Since you're seeing it today, and not 186x, then it's better to know what's going on now. Battlefields are outdoor affairs, and there's been 100 years of rain, wind, heat and all the rest.
Trees grow and die.
Even rivers change course. So when you look, you have to be careful to understand what you're actually seeing. Each battle has some key elements dictated by terrain. Shelby Foote says to view the battlefields in the same season as the battle to get the foliage right. This might be good advice for the purist, but it's much better to travel when nobody else does.