Quote Originally Posted by Caerfanan
EDIT: Oh, maybe just for the initial charge?
Because units in Wedge formation have both a higher attack value and a lower defense value, it's generally best to use Wedge in flanking maneuvers, as this will decrease your units' vulnerability. Attacking head-on in Wedge formation works as well, but you're going to lose a lot more men that if those same units are hitting the enemy on the sides and/or rear.

Also, Wedge formation seems to be a little more maneuverable than Close formation. In practical terms, this can help you get units out of tight spaces if some of them are being squeezed into an unfavorable position.