Hi Burr, well that's interesting that it makes that kind of result, it seems that it knows that the fillet would become self intersecting there and attempts to do something else.

The problem is the bunching at the top here:




Fillet surfaces are basically like a loft through a bunch of cross-sections, and surface lofting just does not behave well when one side of the loft is all compressed together like that, it will tend to generate those kinds of little ripples and lumps.


The one in MoI solves this by putting in a blend curve at the top so that there isn't a compressed side like that:




- Michael