Unchecking this feature is actually great, especially if you play around small corners (like boats, tiny houses, alleyways) as it prevents your camera from going through physical objects and adjusts it self to keep its focus on your avi.

The problem comes when you try to edit something, and it wont let you cam through the object, same goes for when you are editing your avatar it will limit how close you can get to yourself.

I would suggest when in Edit/Build and Edit Appearance modes, camera constraints are automatically disabled.