It depends what you mean by a chimplike profile, because there's two main causes which have different effects, both of which could be described as chimplike. According to Gunson, a chimplike profile usually occurs where the vector of maxillary advancement is happening above the vermillion of the lip. This is why CCW or simply concurrent downgrafting helps mitigate it. This will create a profile with excess philtrum fullness. This is different from someone who gets a 'chimplike' profile from simple over advancement. Over advancement leads to the mouth area in general becoming too heavy for the face, as a LF1 moves only the lower portion of the maxilla in isolation. Philtrum fullness is worse. Obviously both at the same time creates an additive effect. The 'heavy mouth' look is difficult to tackle even with concurrent advancement of the orbito-zygomatic complex because the frontal process of the maxilla is left behind.
