>>At any rate, it certainly looks like the scaling rail boosts up the potential of sweep by quite a bit.<<

I completely agree, I was amazed that it did so much with a relatively sparse amount of curve geometry.

With a network surface, if you only used one side rail it would get all whacked out...the reason I mirrored
the scaling rail was to be able to make the curve's end at the base tangent to the other side, so that
the implicit symmetry of the sweep created a smooth juncture at the point of singularity

I know I'll be experimenting to find other ways to take advantage of this tool's versatility... thanks for being a NURB's genius! :-)

-Jesse