Most settings don’t produce smooth results. Particularly with magnification, all sorts of bad things happen. I’ll post movies of all results soon. My methodology is:

• Create a 100 frame movie
• Create keyframes at 1, 40, and 100
• Start with default at frame 1; mild change of parameter at frame 40; large change of parameter at 100
• Modify keyframe curve types (straight or curved interpolations) at each of 1, 40, and 100. Save UPR for variation. Render movie.

Most of the time, you’ll see the transition, which is rarely desirable. You either want smooth, or discontinuous. I can hardly think of a time where you want continuous but with an obvious transition.

I’m still rendering test cases.