2.1.1271 Part 1 Section 20.1.5.6, contourClr (Contour Color)

a.   The standard allows contour width to be zero.

In Office, if the contour width is zero, the color specified by this element is ignored.

b.   The standard does not describe the interaction between contours and extrusions.

In Office, the contour of a shape is a solid filled line which surrounds the outer edges of the shape, and the outline edges of the extrusion.