Hi Michael, agreed, the boolean was more meant as an approximation to illustrate the desired result.

The path is planar, and rotation is set to freeform.

Good idea about arraying boundary points, I'll give that a try.

Meanwhile I got some interesting results by sweeping each of the edges of just one of the faces along the same path. I then Boolean merged all the resulting 4 surfaces with each other and deleted the "hidden" faces. The boolean intersections don't all work because the faces intersect in complex ways and at very shallow angles. But resulting shape nicely covers the array of the source face, except for the concave section in the middle.