You could always create two 2-point splines, instead of one 3-point spline. That would give you control over each side independently.
if you watch closely, the handles on either side of that point are not independant. when you are dragging one around, the other is also changing. this has something to do with the math for making the spline.
as Eric says, if you need independant control, use 2 splines.
Yep, I realize I can create two separate splines I was more curious if there was something I was missing that would allow me to do it with a single spline and dimension the handles separately, ultimately resulting in less features down the road.
Dragging one handle does change the other side slightly, but I can still manipulate either one independently to get the desired ratio for both. Once I add the dimension it constrains both and you're stuck with the ratio it was when you added the dimension. Didn't seem logical to me...
Thanks for the replies, I guess I'm stuck making separate splines or leaving the handles unconstrained.