I'm not sure anyone knows the answer to that question, Ken. When you cross orchids, just like people, you can get the best of both, the worst of both or something in between. Mine is a little lighter than the regular one but I would have never called it an alba. C. lueddemanniana is an old species known for its nice form. There must be a thousand varieties out there and they all vary in color. The same is true of E. tampensis. I recently posted a nice picture of mine in full bloom. Then I posted another which is called (alba X semi-alba). They look identical to me. The Psychopsis alba is as yellow as it can be. So, it is buyer beware. That is why I like to buy at shows where I can see what I'm getting.
Jim