Both entertaining AND informative, Wiz.
But for your error in writing "guaranteed" when you meant "required" I was with you all the way.
My only experience of CatIII ops has been here in Europe, as I left Oz before CatIII was available there. European ops have always specified Cat IIIa as having a decision height of at least 50 feet, so I wasn't aware of no decision height Cat IIIa ops (min vis 175m) in other places around the world either.