Interesting pattern in soluble support material

[jsw 15]

I'm putting this in the Cura section for lack of a better section, and due to the fact that the travel path for the support material was indeed plotted using Cura.

 

Here's something I've never seen before.  Has anyone seen anything like it?  Nothing appears to be wrong, just interesting.

 

This print is the bottom part of a case which has four round 'feet' a few millimeters high on the bottom surface.  As expected, only the bottoms of the feet are actually touching the build plate and the rest of the bottom surface of the print is supported by a 'raft' (for the lack of a better term) of support material.

 

As expected, the bottom several layers of support material were laid down very sparse, in a crosshatch pattern, and the feet were laid down with the solid bottom layers and expected gyroid fill pattern.

 

I expected that as the first fully-solid layer was approached, the support material lay-down would transition to a more dense pattern to better support the bottom of the case, but I was surprised to see a 'leaf' pattern as shown in the attached image.  This layer took a long time to lay down, and I watched and in many places the extruder did indeed 'trace' the outlines of the leaves.

 

On inspection, the 'leaves' all point to discontinuities in the first solid layer, both the feet and four bolt holes, two of which are placed very near the front two feet and thus do not generate their own 'leaves' in the pattern.

 

I'm curious as to if anyone else has seen this.