I use CATIA (I work for an automotive supplier and work on both Chrysler and Mercedes products -- both use CATIA -- er, rather, DaimlerChrylser uses CATIA.) I haven't used AutoCAD in a long while, but there has to be some way to do it. Look through all the curve, arc, and spline functions and see if anything looks good. At the very least, I would think you could create 3-point arcs. Make one arc thru the first 3 points, then move over one point and make an arc thru the next 3 points, etc. You will get overlapping curves, but the approximation should be good enough to run the saw down the middle. Even Nick in his book say to just play connect-the-dots on paper and smooth a bit as you cut; the strips will only touch the forms at points even if you have perfectly smooth forms.

Dean