Entanglement

It never took Kenshin long to come up with his decisions on the battlefield. He would pause for minutes at a time to think, and to come up with certain ideas after placing himself in his opponent's shoes, so that he would be prepared no matter what that reaction might be. In that preparation, he would quickly overwhelm the opponent, having already considered his response before he began his movements in the first place.

Kenshin knew his advantages well and he knew his men and now he knew Gengyo's. To the untrained man, the Uesugi bowman might have been considered useless, for they were hopelessly outranged, and at the point that they did indeed try to get closer, they would be massacred. But in their presence, they controlled space, they limited the opponent's movements even if they could not attack him directly, all of that pointed towards an advantage.