Closed Polysurface with Holes

I opened an previous version of a file I was working on and found this “solid” in it. It has these two holes.

Everything I have tried tells me this is a good polysurface.

I presume this is a bug so I share. I have no idea how I created this. However, there supports to be surfaces extending from where the holes are similar, but large then then bent pipe to the left.

Problem Holes.3dm (6.9 MB)

Hello - there are two coincident surfaces there.


In playing with the file I was able to find the source of the problem:
Problem Holes 2.3dm (3.7 MB)

Here is the starting point of the problem. There un unjoined edge between the upper and lower sections. Doing CAP on this produces two surfaces.