I was sculpting (3d coat 4.8.0.6, tested on 4.8.0.3 aswell same result) and realized the pinch brush was really not acting like I expected, I checked the wireframe and quickly understood, there was no pinching to the pinch brush :). Don't know if this is a mislabelled brush or if it's a bug, bug you expect pinching to happen when using the pinch brush (and it's one of the most important type of brush in 3d sculpting) it was carving but not pinching at all, it's like something wasn't there and as I said, checking the wireframe it was obvious, the pinching was not happening. Hope it help.