The wedge is also useful for other units besides horse archers if they need to squeeze through a gap in the battle line. Wedge can make them narrow enough to make it through without getting caught in the fighting on either side, then switch back to close and hit the enemy from behind.

Until someone suggested the maneouvering uses for wedge formation I was pretty disappointed with it. As I understand it it was used (primarily by cavalry) to dig into a unit from the front and then "explode laterally," effectively flanking it from within without having to get around the side. But in the game the wedge just stops when it hits and becomes pretty useless after that. Oh well.

Also, as far as stats go, one doesn't have to be completely stat-focused or completely play-focused. It's possible to balance the two outlooks on the game, and I think that's what most players do. Stats are meaningful for understanding the game's mechanics, but are not the final word (at least not in TW).