> I my terms, I think you would be suggesting to try out those alternatives if all else fails?

I guess the best way to sum it up would be to try those options if you want something that is less "mechanical" than a regular circular cross-section fillet.

The blend options can give a more "organic" type of rounded piece.

With the exact circular cross-section, the fillet itself tends to draw some attention to itself, I mean that it tends to be more recognizable as a mechanical rounded thing. The blending styles can help to make the blend appear more seamless between things, like they are more one continuous skin.

For example if you were working on a dinosaur and had a surface for the dinosaur's leg that you wanted to join with the dinosaur's body, and then wanted to round out the sharp edge between these 2 pieces, that's the kind of thing that you would want to use a blend for instead of a circular fillet, because dinosaurs don't have exact circle shapes in them.

- Michael