I completely agree that one hardly qualifies for the other. The two programs do have quite a bit in common but a large portion of a comprehensive VT curriculum focuses on subjects that the CWI body of knowledge doesn't touch upon: optics, light properties, light manipulation, profilometers, remote viewing, comparators, surface textures, coatings, reflection/refraction... etc.
The CWI and VT programs supplement each other very well, but not when one is simply handed out without qualification through examination.