Hi Brian,

re:
> Can the MoI properties of tangents and derivatives, etc., of a curve be used to investigate the
> rotation frame(s) of the spiral target curve?

Not quite, the rotation of a sweep frame is another thing, look up "Bishop Frame" for references.

Bishop, R. L. "There is more than one way to frame a curve.",
American Mathematical Monthly (1975) pp. 245-251

The intrinsic "Frenet frame" of the curve formed by the tangent and curvature vectors does not work well using it for sweep frame rotation.

- Michael