Well, using your forehead to hit the cheekbone of someone is a very effective strategy when trying to hurt an opponent, and if you look at the replay, DuToit first intends to clear, but clearly sees Danty in the way, puts his right hand on the the floor to extend the momentum and hit full blast on Danty's face...
You can argue his initial intention is to clear the ball, but he does it head first. To be honest, Allende just alongside him does exactly the same movement, he is just lucky there is no face in front of him, just Aldritt standing up and getting the hit on his shoulder...
