Well whatever the case may be for the engagement at Gettysburg a number of things certainly could have been done better.I'm not so sure about this, despite Lee's after action report that made the battle sound like an accident. I suspect he was being somewhat disingenuous. There were four Confederate divisions marching toward Gettysburg on the morning of July 1. They weren't all looking for shoes. Possibly none of them were, despite Heth's later claim to the contrary. Lee knew he had to win a quick victory. He had successfully concentrated his army, or expected to at Gettysburg. He thought he could swallow up a small part of Meade's army there. He may not have expected Meade to concentrate at Gettysburg as quickly as Meade did.
- Better artillery placement by the Confederates.
- Better fuses on the Confederate shrapnel, so that they didn't over shoot as much before exploding.
- Better fuses on the Union shrapnel so they didn't overshoot as much before exploding, which by luck hit troops hiding in the woods.
And as luck would have it, a dawn attack with disposition through maybe half the field at night, would have been into the rising sun - blinding the attackers and illuminating the field for the defenders.