i noticed when you put in vertical parabolic curves onto the profile tangents it will ask you if you want length or k.
however depend on which one you specify. it will hold on to that value when it comes to changeing the tangent locations. for what i am doing now i want k by default. but accidentally i put in length because i just went through all the pi's quickly to put in the curves. but i see no control which allows you to control which type to hold. this is a property inside the vertical curve but it's not exposed to user. once you create by length that's it. until you delete the curve and re enter using k then it will hold k.
know what i am saying?
Civil 3D 2012 Work: Xeon W3503, 12GB, Quadro 2000, Dell P2211H x 2 Home: 3930k, 12GB, GTX 590, U3011, QX2710