Loetz Phanomen Genre 377 vase

Here is an example of the "attribution" game. I bought this vase on ebay, and it was sold as "Bohemian Art Glass" which is correct. But if it had been sold as "Loetz Phanomen 377" it might have sold for more. The real question is; am I right? Is this really Loetz 377? I have compared it to the beautiful photographs in "Loetz Austria 1900" (Waltraud Neuwirth) and to the fine examples on Loetz.com and I came to the conclusion that it is Loetz Phanomen Gre-377. It has all the quality and color and the shape is right, so by Dr. Alfredo's method I would say I'm on firm ground here. If anyone has an alternate theory (attribution) I am all ears. This is a simple but elegant piece, and it is also one of my favorites.