[quote user="caddcop"]When I trued to define a profile for that 2D line based upon the back of curb and my needed cross slope, the zigs and zags of the curb make that profile look "lumpy" because the slope is calculated perpendicular to the curb, instead of the actual road profile.[/quote]
Which tool did you use to make the projection? As I said, some of them project perpendicular from the source, and some project perpendicular to the target. Try using a different tool, or a different option on the same tool. (I think Project Profile To Element projects perpendicular to the target, and that sounds like it's what you want. I think Project Profile Range To Element does the same, over an interval.)
In case nothing else works, consider projecting the whole element wholesale and where the projection is lumpy, project the parallel segments separately (over appropriate ranges) and connect the points.
[quote user="caddcop"]My alternative approach is to make a dummy profile for the 2D line and create a sidewalk only template that ties its horizontal location to the 2D line and actually gets its vertical component from a slope constrain to the far edge. And the far edge of the sidewalk uses the back of curb as its Horizontal and Vertical control. The resulting corridor will be constructed perpendicular from my 2D line and the slope of the sidewalk will be from the back of curb at my needed slope to some elevation at a point along my 2D line.[/quote]
Interesting. It's a little difficult to parse what you're saying here, but at the risk of being entirely redundant, consider setting up a point within your sidewalk-only template to represent your centerline (or whatever element you want your profile along). This point need not belong to a component, but it should be locked by vertical (or slope, as may be appropriate) to your sidewalk point. Then use a point control to peg horizontal only to match your centerline. Then project that new linear feature's profile to your actual centerline.
I just realized that what I was suggesting is exactly what you get when you project perpendicular to the sidewalk instead of perpendicular to the centerline. On the other hand, if you rearrange what I said there, where you have the corridor based on your centerline, and establish the lateral and vertical position in whatever way makes sense, then you could project that (using a point within your template) to the centerline and have your profile that way. I hope that makes sense.