Your answer was totally unresponsive, bordering on spam IMHO.

The answer is more like, well GPUs can process a lot faster than CPUs so they can calculate more hashes at a faster rate. I don't know about the mathematics about it though but it doesn't seem strange to me. You can tell the GPU to focus on one task while the CPU still has to run your computer and I believe it has to do with memory usage as well. That's why GPU isn't so great for scrypt mining.