Hi ed, also there are some other tools you can use to help you construct a curve that has the shape you want. The new Transform > Deform > Flow command in v3 may be particularly useful.

That Flow command allows you to remap a curve that follows a straight line to deform it onto a curved path.

For something like I think you're describing, you can use it to make an initial 2D curve that has the rise and fall that you want that has a base line underneath it like this:



So that basically focuses just on making the elevation rise and fall part alone.

Then you can create an additional path curve in the Top view something like this:




Now you can select your inital "rise and fall" curve, and run Transform > Deform > Flow, pick the line underneath it as the base curve, and the curved path that was drawn in the top view as the target and it will generate a curve like this:




Doing it that way will allow you to kind of focus on the rise and fall and the path as separate components and that may be a lot easier than doing stuff like individual control point manipulation directly on the 3D curve.

But it will all come down to you creating a curve that has the shape you want - if you want to control the shape of the edge of the surface to have some particular qualities, you can make that happen by making a curve that has that kind of shape and using that curve to generate the surface as I showed before.

- Michael