If you have a "C" channel shape (for example) and drill a THRU hole in one
of the short legs of the "C" so that it goes through the other leg, although
you "see" two individual holes, Inventor only sees a single hole that
happens to go through two faces.
When flattened, the other face is no longer "hit" by the axis of the hole.
A possible reason that you aren't seeing all you should?
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