What it's telling you is pretty obvious: that your graphics card would probably perform better with a more powerful CPU according to a certain set of tests which will give an indication of how it will perform in real life, and it doesn't claim to tell you anymore than that, so I don't understand what you are getting so worked up about?
It's also blinding obvious that the CPU will be more of a bottleneck in scenarios where the bulk of the load is on the CPU, surely?
Given that these figures are meaningless to you how, when you buy a new computer, do you intend to divine the best setup for your needs?
I can guess your answer to that based on previous experience but in my opinion the real world experience of those doing the same/similar is the best guide, which is precisely why I offered my experience with an identical card to the OP. Bottleneck Calculator was an aside with the caveat that it wasn't entirely appropriate for Trainz before you interjected, seemingly with a crusade against it.
