I definitely agree with it being a useful model, after all that is the the way GPUs are presented to programmers. But when getting into detailed performance comparisons, especially with CPUs, that simplified model breaks down quickly and becomes a hindrance. Which is why I think it's unfortunate that NVidia (deliberately) uses the term "core" that leads people to believe they can make a direct comparison to CPUs. Comparisons that coincidentally lead people to believe GPUs are much more special than they actually are.